JP2006198466A - Photocatalytic sheet and illumination device using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sheet having flexibility, incombustibility and photocatalysis and an illumination device using the sheet. <P>SOLUTION: This photocatalytic sheet is composed of a light-diffusible base material, an intermediate layer arranged on the base material and a photocatalyst layer arranged on the intermediate layer. When a mandrel test is applied to this photocatalytic sheet, the minimum radius of a mandrel, which does not generate a crack on the intermediate and photocatalyst layers, is ≤10 mm. The photocatalyst layer is formed from at least one silane compound (A) selected from the group consisting of the organosilanes shown by formula (1): (R<SP>1</SP>)<SB>n</SB>Si(OR<SP>2</SP>)<SB>4-n</SB>, hydrolysates of the organosilanes and condensates of the organosilanes and a photocatalyst composition (B) containing a photocatalyst. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a sheet having flexibility, incombustibility, light diffusibility, and photocatalysis, and an illumination device using the sheet.

  In many cases, an illumination cover capable of diffusing light is attached to a home lighting device in order to soften light from a light source. In conventional lighting covers, acrylic resin sheets have been generally used, but in recent years, inorganic sheets based on glass fiber fabrics have been used (Patent Document 1). However, there has been a problem that the surface of such a lighting cover, in particular, the surface of a lighting cover made of glass fiber fabric as a base material, is easily contaminated with cigarette dust and the like, and the illuminance decreases.

  On the other hand, building materials such as walls and ceilings that have a photocatalytic layer on the surface of the substrate have been proposed in order to decompose and remove dirt such as tobacco dust and harmful substances such as formaldehyde, which is the cause of sick house syndrome. (Patent Document 2). In this case, the light from the light source is directly irradiated to the side opposite to the substrate, that is, the photocatalyst layer.

  However, in the case of a lighting device with a lighting cover, dirt or the like adheres to the outside of the lighting cover, that is, the side opposite to the light source. Therefore, in order to disassemble and remove dirt using the photocatalytic function, the side opposite to the light source is used. It was necessary to form a photocatalyst layer on the surface of the substrate. For this reason, the base material with high light transmittance was used, for example, the transparent glass plate was used (patent document 3).

  However, the glass plate is not flexible and is not suitable for a molded product having a bent portion such as a lighting cover, and the use of a photocatalytic molded product using an inorganic material as a base material is limited to a window glass or the like. .

The photocatalyst layer is usually formed by applying a photocatalyst composition containing a photocatalyst substance and a binder component for fixing the photocatalyst material on a substrate. When the substrate does not have flexibility, there is no problem, but when the photocatalyst layer is formed on a flexible substrate, cracks may occur at the bent portion depending on the binder.
JP 2001-55646 A Japanese Patent Laid-Open No. 2004-300648 JP 2001-287972 A

  The present invention is intended to solve the problems associated with the prior art as described above, and provides a sheet having flexibility and incombustibility and having a photocatalytic action, and a lighting device using the sheet. The purpose is that.

  As a result of earnest research to solve the above problems, the present inventor, as long as the substrate is light diffusive, the photocatalyst layer formed on the surface is irradiated with light from the substrate side. Has also been found to exhibit a photocatalytic action and to decompose and remove harmful substances attached to the photocatalyst layer. In addition, the photocatalytic sheet obtained by coating a photocatalytic composition containing a bifunctional to tetrafunctional silane compound on a flexible substrate is less prone to cracks on its surface and has excellent moldability such as bending. The headline and the present invention were completed.

That is, the photocatalytic sheet according to the present invention is a photocatalytic sheet comprising a base material having light diffusibility, an intermediate layer provided on the base material, and a photocatalytic layer provided on the intermediate layer,
In the mandrel test, the photocatalytic sheet has a minimum radius of a mandrel in which cracks do not occur in the intermediate layer and the photocatalyst layer of 10 mm or less,
The photocatalytic layer is
(A) The following formula (1)
(R ¹ ) _n Si (OR ² ) _4-n (1)
(In the formula, R ¹ represents a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms, and when a plurality of R ¹ exist, they may be the same or different. R ² has 1 carbon atom. Represents an alkyl group of ˜5, an acyl group of 1 to 6 carbon atoms or a phenyl group, n is an integer of 0 to 2).
And at least one silane compound selected from the group consisting of a hydrolyzate of the organosilane and a condensate of the organosilane, and (B) a photocatalyst composition containing a photocatalyst. It is characterized by being a layer.

The substrate is preferably a fluororesin sheet containing fine particles, a silicone resin sheet containing fine particles, or a glass fiber fabric.
N in the formula (1) is preferably 1 or 2.

The photocatalyst composition preferably further includes a polymer (C) containing a silyl group having a silicon atom bonded to a hydrolyzable group and / or a hydroxyl group, and has a SiO bond and a weight average molecular weight. It is also preferable to contain 300-100,000 organosiloxane oligomer (D). This organosiloxane oligomer (D) has the following formula (2)
-(RO) _p- (R'O) _q- R "(2)
(In the formula, R and R ′ each independently represent an alkyl group having 1 to 5 carbon atoms, R ″ represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and p and q each have a value of p + q. 2 to 50).

The photocatalytic composition further comprises:
(E) The following formula (3)
(R ³ ) _m Ti (OR ⁴ ) _4-m (3)
(Wherein R ³ represents an organic group having 1 to 8 carbon atoms, and when there are a plurality of them, they may be the same or different, and R ⁴ is an alkyl group having 1 to 6 carbon atoms, It represents an organic group selected from the group consisting of an acyl group having 1 to 6 carbon atoms and a phenyl group, and when there are a plurality of them, they may be the same or different, and R ³ and R ⁴ are the same Or m may be an integer of 0 to 3)
A titanium alcoholate, a hydrolyzate of the titanium alcoholate, a condensate of the titanium alcoholate and a condensate of the chelate compound of the titanium alcoholate, and a titanium acylate represented by the above formula (1), It is preferable to contain at least one titanium compound selected from the group consisting of a hydrolyzate of the titanium acylate, a condensate of the titanium acylate and a condensate of the chelate compound of the titanium acylate.

The intermediate layer has the following formula (1)
(R ¹ ) _n Si (OR ² ) _4-n (1)
(In the formula, R ¹ represents a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms, and when a plurality of R ¹ exist, they may be the same or different. R ² has 1 carbon atom. Represents an alkyl group of ˜5, an acyl group of 1 to 6 carbon atoms or a phenyl group, n is an integer of 0 to 2).
And at least one silane compound selected from the group consisting of organosilane hydrolysates and organosilane partial condensates, and hydrolyzable groups and / or silicon bonded to hydroxyl groups It is preferable to include a layer formed from a coating composition for an undercoat containing a polymer containing a silyl group having an atom.

The total light transmittance of the substrate is preferably 40% or more, and the parallel light transmittance is preferably 5% or less.
The photocatalytic sheet according to the present invention preferably has a fluororesin layer between the intermediate layer and the base material.

An illumination device according to the present invention is an illumination device including an artificial light source and an illumination cover in which the photocatalytic sheet is fixed to a support,
An artificial light source and an illumination cover are provided so that the base material of the photocatalytic sheet exists between the artificial light source and the photocatalytic layer of the photocatalytic sheet.

  According to the present invention, a sheet having flexibility and incombustibility and having a photocatalytic action, and a lighting device using this sheet can be obtained.

<Photocatalyst composition>
First, each component of the photocatalyst composition used in the present invention will be described.
(A) Silane compound:
The silane compound (A) used in the present invention has the following formula (1):
(R ¹ ) _n Si (OR ² ) _4-n (1)
(In the formula, R ¹ represents a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms, and when a plurality of R ¹ exist, they may be the same or different. R ² has 1 carbon atom. Represents an alkyl group of ˜5, an acyl group of 1 to 6 carbon atoms or a phenyl group, n is an integer of 0 to 2).
At least one selected from the group consisting of an organosilane (hereinafter referred to as “organosilane (1)”), a hydrolyzate of the organosilane (1), and a condensate of the organosilane (1) This is a silane compound. This silane compound (A) acts as a binder. Moreover, it is preferable that n of said Formula (1) is 1 or 2 at the point by which a flexible photocatalyst layer is formed.

  The silane compound (A) used in the present invention is at least one silane compound selected from the group consisting of organosilane (1), hydrolyzate of organosilane (1), and condensate of organosilane (1). Of these three silane compounds, only one silane compound may be used, any two silane compounds may be mixed, or all three silane compounds may be mixed. May be used.

In the above formula (1), R ¹ is a monovalent organic group having 1 to 10 carbon atoms, specifically,
Methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, i-butyl group, sec-butyl group, t-butyl group, n-pentyl group, n-hexyl group, n-heptyl group Alkyl groups such as n-octyl group and 2-ethylhexyl group;
Acyl groups such as formyl group, acetyl group, propionyl group, butyryl group, valeryl group, benzoyl group, trioyl group, caproyl group;
Examples thereof include a vinyl group, an allyl group, a cyclohexyl group, a phenyl group, an epoxy group, a glycidyl group, a (meth) acryloxy group, a ureido group, an amide group, a fluoroacetamide group, and an isocyanate group.

Furthermore, examples of R ¹ include substituted derivatives of the above organic groups. Examples of the substituent of the substituted derivative of R ¹ include a halogen atom, a substituted or unsubstituted amino group, a hydroxyl group, a mercapto group, an isocyanate group, a glycidoxy group, a 3,4-epoxycyclohexyl group, a (meth) acryloxy group, A ureido group, an ammonium base, etc. are mentioned. However, the number of carbon atoms of R ¹ composed of these substituted derivatives is preferably 10 or less including the carbon atoms in the substituent. When a plurality of R ¹ are present in the formula (1), they may be the same or different.

Examples of R ² which is an alkyl group having 1 to 5 carbon atoms include a methyl group, an ethyl group, and n
-Propyl group, i-propyl group, n-butyl group, sec-butyl group, t-butyl group, n-pentyl group and the like can be mentioned, and as R ⁴ which is an acyl group having 1 to 6 carbon atoms Is
Examples include formyl group, acetyl group, propionyl group, butyryl group, valeryl group, caproyl group and the like. When a plurality of R ² are present in the formula (1), they may be the same or different from each other.

Examples of the organosilane (1) in which n in the formula (1) is 0 include tetramethoxysilane, tetraethoxysilane, tetra-n-propoxysilane, tetra-i-propoxysilane, tetra-n-butoxysilane and the like. Alkoxysilanes;
Examples of the organosilane (1) in which n in the above formula (1) is 1 include methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, n-propyltrimethoxysilane, n-propyltrimethoxysilane. Ethoxysilane, i-propyltrimethoxysilane, i-propyltriethoxysilane, n-butyltrimethoxysilane, n-butyltriethoxysilane, n-pentyltrimethoxysilane, n-pentyltriethoxysilane, n-hexyltrimethoxy Silane, n-heptyltrimethoxysilane, n-octyltrimethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, cyclohexyltrimethoxysilane, cyclohexyltriethoxysilane, phenyltrimethoxysilane, phenyl Ethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropyltriethoxysilane, 3-chloropropyltrimethoxysilane, 3-chloropropyltri Ethoxysilane, 3,3,3-trifluoropropyltrimethoxysilane, 3,3,3-trifluoropropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 2-hydroxyethyltri Methoxysilane, 2-hydroxyethyltriethoxysilane, 2-hydroxypropyltrimethoxysilane, 2-hydroxypropyltriethoxysilane, 3-hydroxypropyltrimethoxysilane, 3-hydroxypropyltriethoxysilane, 3-mercaptopropi Trimethoxysilane, 3-mercaptopropyltriethoxysilane, 3-isocyanatopropyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltriethoxysilane, 3- (meth) acryloxypropyltrimethoxysilane, 3- (meth) acryloxypropyltriethoxy Silane, 3-ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, allyltrimethoxysilane, vinyltriacetoxysilane, etc. Trialkoxysilanes; methyltriacetyloxysilane, methyltriphenoxysilane, and the like.

Examples of the organosilane (1) in which n in the formula (1) is 2 include dimethyldimethoxysilane, dimethyldiethoxysilane, diethyldimethoxysilane, diethyldiethoxysilane, di-n-propyldimethoxysilane, and di-n-propyl. Diethoxysilane, di-i-propyldimethoxysilane, di-i-propyldiethoxysilane, di-n-butyldimethoxysilane, di-n-butyldiethoxysilane, di-n-pentyldimethoxysilane, di-
n-pentyldiethoxysilane, di-n-hexyldimethoxysilane, di-n-hexyldiethoxysilane, di-n-heptyldimethoxysilane, di-n-heptyldiethoxysilane, di-n-octyldimethoxysilane, di -N-octyldiethoxysilane, di-n-cyclohexyldimethoxysilane, di-n-cyclohexyldiethoxysilane, diphenyldimethoxysilane, diphenyldiethoxysilane, methylethyldimethoxysilane, methylethyldiethoxysilane, n-pentylmethyl Dimethoxysilane, n-pentyl methyldiethoxysilane, cyclohexyl methyldimethoxysilane, cyclohexyl methyldiethoxysilane, phenyl methyldimethoxysilane, phenyl methyldiethoxysilane, 3-glycid Cypropylmethyldimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 2- (3,4-epoxycyclohexyl) ethylmethyldimethoxysilane, 2- (3,4-epoxycyclohexyl) ethylmethyldiethoxysilane, 3- Glycidoxypropylethyldimethoxysilane, 3-glycidoxypropylethyldiethoxysilane, 2- (3,4-epoxycyclohexyl) ethylethyldimethoxysilane, 2- (3,4-epoxycyclohexyl) ethylethyldiethoxysilane, Dialkoxysilanes such as 3-aminopropylmethyldimethoxysilane and 3-aminopropylethyldiethoxysilane; dimethyldiacetyloxysilane, dimethyldiphenoxysilane and the like.

These organosilanes may be used alone or in combination of two or more.
Of the above organosilanes, dialkoxysilanes and trialkoxysilanes are preferred, trialkoxysilanes are more preferred, methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, 3-glycid Xylpropyltrimethoxysilane and 3-glycidoxypropyltriethoxysilane are particularly preferred.

  In the present invention, organosilane (1) may be used as it is as silane compound (A), but hydrolyzate and / or condensate of organosilane (1) can be used.

The hydrolyzate of organosilane (1) is sufficient if at least one of ² to 4 OR ² groups contained in organosilane (1) is hydrolyzed. For example, one OR ² group May be hydrolyzed, two OR ² groups may be hydrolyzed, three OR ² groups may be hydrolyzed, or any mixture thereof.

  The organosilane (1) condensate is a product in which the silanol groups in the hydrolyzate produced by hydrolysis of the organosilane (1) are condensed to form Si—O—Si bonds. In the present invention, it is not necessary that all of the silanol groups are condensed, and the condensate may be one obtained by condensing a small part of silanol groups, one containing most (including all) silanol groups, And mixtures thereof.

  Such hydrolyzate and / or condensate of organosilane (1) can be produced by hydrolyzing and condensing organosilane (1) in advance. In addition, as described later, when preparing the photocatalyst composition, hydrolyzate and / or condensate of organosilane (1) is prepared by hydrolyzing and condensing organosilane (1) and water. You can also. In addition, you may add this water independently, and you may use the water contained in a photocatalyst (B) or the water or organic solvent mentioned later. The amount of water when added independently is usually 0.5 to 5 mol, preferably 0.7 to 3 mol, particularly preferably 0.7 to 2 mol, relative to 1 mol of organosilane (1). Is desirable.

As such a condensate of organosilane (1), the polystyrene-reduced weight average molecular weight (hereinafter referred to as “Mw”) by GPC method is usually 300 to 100,000, preferably 500 to 100,000. Preferably, a condensate of 800 to 100,000, more preferably 1,000 to 50,000, particularly preferably 2,000 to 30,000 is used.

  When the condensate of organosilane (1) is used as the silane compound (A) in the present invention, it may be prepared from the organosilane (1) or a commercially available condensate of organosilane. Commercially available organosilane condensates include MKC silicate manufactured by Mitsubishi Chemical, ethyl silicate manufactured by Colcoat, silicone resin manufactured by Toray Dow Corning Silicone, silicone resin manufactured by GE Toshiba Silicone, Shin-Etsu Chemical Examples include silicone resins and silicone oligomers manufactured by Kogyo Co., Ltd., hydroxyl group-containing polydimethylsiloxane manufactured by Dow Corning Asia, and silicone oligomers manufactured by Nihon Unicar. These commercially available condensates of organosilane may be used as they are, or may be further condensed.

Such silane compounds (A) may be used singly or in combination of two or more.
In the photocatalyst composition used in the present invention, the silane compound (A) is 5% by weight or more and 95% by weight in terms of complete hydrolysis condensate with respect to the solid content of the photocatalyst composition excluding the photocatalyst (B). % Or less, preferably 10 to 90% by weight, more preferably 20 to 80% by weight. Here, the completely hydrolyzed condensate means that the OR ² group in the above formula (1) is hydrolyzed to 100% to become a Si—OH group, and S
The i-OH group is completely condensed to form a siloxane structure. When the content of the silane compound (A) is less than the above lower limit, the formed coating film is brittle, and choking or the like may occur.

  In the photocatalyst composition used in the present invention, the total amount of the bifunctional and trifunctional silane compounds is 90% by weight or more, preferably 95% by weight or more based on the entire silane compound (A). Is preferred. When these bifunctional and trifunctional silane compounds are in the above range, the resulting photocatalyst layer has good flexibility and is unlikely to crack.

(B) Photocatalyst:
Examples of the photocatalyst (B) used in the present invention include semiconductor powder and / or sol having photocatalytic activity. Examples of the semiconductor having photocatalytic activity include TiO ₂ , TiO ₃ , SrTiO ₃ , FeTiO ₃ , WO ₃ , SnO ₂ , Bi ₂ O ₃ , In ₂ O ₃ , ZnO, Fe ₂ O ₃ , RuO ₂ , CdO, CdS, CdSe, GaP, GaAs, CdFeO ₃ , MoS ₂ , L
Examples include aRhO ₃ , GaN, CdP, ZnS, ZnSe, ZnTe, Nb ₂ O ₅ , ZrO ₂ , InP, GaAsP, InGaAlP, AlGaAs, PbS, InAs, PbSe, and InSb. Moreover, as a photocatalyst (B), the titanium oxide which has platinum compounds, such as what carried the platinum compound on the titanium oxide surface, and the titanium oxide manufactured by making a platinum compound coexist can also be mentioned. Examples of the platinum compound include platinum alone and the halogenated platinum compounds described in JP-A-2002-239395. Of these, TiO ₂ , ZnO, and titanium oxide having a platinum compound are preferred. In the present invention, due to the photocatalytic ability of the photocatalyst (B), the surface of the photocatalyst layer becomes hydrophilic in a short time even with weak light, and as a result, the photocatalyst layer resistance is not substantially impaired. It became clear that the contamination could be improved significantly. In addition, in the photocatalyst layer formed from the photocatalyst composition, the photocatalyst (B) is co-condensed with the silane compound (A) and the like, and the hydrophilicity and stain resistance of the photocatalyst layer are maintained for a long time.

The semiconductor is desirably used in the form of powder and / or sol. Specifically, it is desirable to take any one of three forms: powder, an aqueous sol dispersed in water, a polar solvent such as isopropyl alcohol, and a solvent sol dispersed in a nonpolar solvent such as toluene. In the case of a solvent-based sol, depending on the dispersibility of the semiconductor, it may be further diluted with water or a solvent. The average particle size of the semiconductor in these forms is preferably as small as possible from the viewpoint of photocatalytic activity. In this case, if the average particle size of the semiconductor is 0.1 to 0.5 μm, the photocatalytic layer tends to become opaque due to the light concealing action of the semiconductor, and if it is 0.05 to 0.1 μm, the photocatalytic layer tends to become translucent. Furthermore, when it is 0.05 μm or less, the photocatalyst layer tends to be transparent. Therefore, the average particle diameter of the semiconductor can be appropriately selected according to the use of the photocatalytic sheet.

  When the photocatalyst (B) is an aqueous sol or a solvent-based sol, the solid content concentration is preferably more than 0% by weight and 50% by weight or less, more preferably more than 0% by weight and 40% by weight or less.

  As a method of blending the photocatalyst (B) in the photocatalyst composition, it may be added after preparing a composition comprising the silane compound (A) and the components (C) to (E) described later, or A photocatalyst (B) is added together with the silane compound (A) and components (C) to (E) described later to prepare a photocatalyst composition, and in the presence of the photocatalyst (B), the silane compound (A) and the like. Can also be hydrolyzed and condensed. When the photocatalyst (B) is added together with the silane compound (A) and components (C) to (E) described later, the semiconductor compound can be co-condensed with the silane compound (A) and the like, and the durability of the resulting photocatalyst layer Especially improved. When the photocatalyst (B) is an aqueous dispersion, it is preferable to add the photocatalyst (B) together with the silane compound (A) and the components (C) to (E) described later, and further, the stability described later. Even when the viscosity of the photocatalyst composition is increased by blending the property improver, it is preferable to add the photocatalyst (B) together with the silane compound (A) and the components (C) to (E) described later. Further, when the photocatalyst composition is used as an enamel containing a coloring component, the photocatalyst composition may be prepared and then toned, and the silane compound (A) and (C) to (to be described later) E) The photocatalyst (B) and the coloring component may be added simultaneously to a composition comprising the component.

  As a photocatalyst (B) used for this invention, it is preferable to use the aqueous dispersion whose pH is 3-9 so that it may mention later. When an aqueous dispersion of a photocatalyst having a pH of 3 to 9 is used, a photocatalyst composition having little environmental problems and the like is obtained with little corrosiveness to a machine or the like during production or coating of the resulting photocatalyst composition. In particular, as will be described later, in the presence of an aqueous dispersion having a pH of 3 to 9 and an organic solvent having a surface tension at 20 ° C. exceeding 260 μN / cm of 20% by weight or less, the silane compound (A) Etc. are preferably hydrolyzed and condensed. As a result, the photocatalyst (B) is co-condensed with the silane compound (A), and the resulting photocatalyst composition is easily dispersed even in relatively hydrophobic alcohols such as i-propyl alcohol and i-butyl alcohol. The wettability with respect to the base material of the photocatalyst composition obtained becomes good, and the film formability of the photocatalyst layer is excellent. Moreover, the photocatalyst composition which is excellent also in storage stability is obtained.

  In this invention, a photocatalyst (B) can be used individually or in mixture of 2 or more types. The photocatalyst (B) is contained in the photocatalyst composition in an amount of 1 to 90% by weight, preferably 15 to 85% by weight, more preferably 25 to 80% by weight, based on the total solid content of the composition. It is desirable to contain. If the amount of the photocatalyst (B) is less than the lower limit relative to the total solid content of the photocatalyst composition, the photocatalytic action may not be exhibited. If the amount exceeds the upper limit, choking or the like may occur when forming the photocatalyst layer. It may occur and the film-forming property may be inferior.

(C) Specific silyl group-containing polymer:
A silyl group-containing polymer (C) having a silicon atom bonded to a hydrolyzable group and / or a hydroxyl group (hereinafter, also simply referred to as “specific silyl group-containing polymer (C)”) comprises a hydrolyzable group and / or Alternatively, it is composed of a polymer having a silyl group having a silicon atom bonded to a hydroxyl group (hereinafter referred to as “specific silyl group”) at the terminal and / or side chain of the polymer molecular chain. The specific silyl group-containing polymer (C) has an excellent coating property when the photocatalyst layer is cured by co-condensing hydrolyzable groups and / or hydroxyl groups in the silyl group with the silane compound (A). It is a component that provides membrane performance. The content of silicon atoms in the specific silyl group-containing polymer (C) is usually 0.001 to 20% by weight, preferably 0.01 to 15% by weight, based on the entire specific silyl group-containing polymer (C). %. A preferred specific silyl group is a group represented by the following formula (4).

(In the formula, X represents a hydrolyzable group such as a halogen atom, an alkoxyl group, an acetoxy group, a phenoxy group, a thioalkoxyl group, an amino group, or a hydroxyl group; R ⁵ represents a hydrogen atom, 1 carbon atom;
Represents an alkyl group having 10 to 10 carbon atoms or an aralkyl group having 1 to 10 carbon atoms, and i is an integer of 1 to 3; )
The specific silyl group-containing polymer (C) can be produced, for example, by the following methods (I) and (II).

  (I) A hydrosilane compound corresponding to the general formula (4) (hereinafter also simply referred to as “hydrosilane compound”) is converted into a vinyl polymer having a carbon-carbon double bond (hereinafter referred to as “unsaturated vinyl polymer”). And the addition reaction to the carbon-carbon double bond.

  (II) The following general formula (5)

(In the formula, X, R ⁵ and i are respectively synonymous with X, R ⁵ and i in the above formula (4), and R ⁶ represents an organic group having a polymerizable double bond)
A method of copolymerizing a silane compound represented by formula (hereinafter referred to as “unsaturated silane compound”) and another vinyl monomer.

  Examples of the hydrosilane compound used in the above method (I) include halogenated silanes such as methyldichlorosilane, trichlorosilane, and phenyldichlorosilane; methyldimethoxysilane, methyldiethoxysilane, phenyldimethoxysilane, Alkoxysilanes such as methoxysilane and triethoxysilane; acyloxysilanes such as methyldiacetoxysilane, phenyldiacetoxysilane and triacetoxysilane; amino such as methyldiaminoxysilane, triaminoxysilane and dimethylaminoxysilane Examples include xylsilanes. These hydrosilane compounds can be used alone or in admixture of two or more.

The unsaturated vinyl polymer used in the method (I) is not particularly limited as long as it is not a polymer having a hydroxyl group. For example, the following methods (I-1) and (I-2) Or it can manufacture by these combinations.

  (I-1) After (co) polymerizing a vinyl monomer having a functional group (hereinafter referred to as “functional group (α)”), the functional group (α) in the (co) polymer By reacting a functional group capable of reacting with the functional group (α) (hereinafter referred to as “functional group (β)”) and an unsaturated compound having a carbon / carbon double bond, the side chain of the polymer molecular chain is reacted. A method for producing an unsaturated vinyl polymer having a carbon-carbon double bond.

  (I-2) A radical polymerization initiator having a functional group (α) (for example, 4,4′-azobis-4-cyanovaleric acid, etc.) is used, or both the radical polymerization initiator and the chain transfer agent are used. Using a compound having a functional group (α) (for example, 4,4′-azobis-4-cyanovaleric acid and dithioglycolic acid), a vinyl monomer is (co) polymerized to form a polymer molecule After synthesizing a (co) polymer having a functional group (α) derived from a radical polymerization initiator or chain transfer agent at one or both ends of the chain, the functional group (α) in the (co) polymer is synthesized. An unsaturated vinyl polymer having a carbon-carbon double bond at one or both ends of a polymer molecular chain by reacting an unsaturated compound having a functional group (β) and a carbon / carbon double bond. How to manufacture.

  Examples of the reaction between the functional group (α) and the functional group (β) in the methods (I-1) and (I-2) include an esterification reaction between a carboxyl group and a hydroxyl group, and a carboxylic anhydride group and a hydroxyl group. Ring-opening esterification reaction, carboxyl group and epoxy group ring-opening esterification reaction, carboxyl group and amino group amidation reaction, carboxylic acid anhydride group and amino group ring-opening amidation reaction, epoxy group Ring-opening addition reaction between a hydroxyl group and an amino group, urethanization reaction between a hydroxyl group and an isocyanate group, a combination of these reactions, and the like.

  Examples of vinyl monomers having a functional group (α) include unsaturated carboxylic acids such as (meth) acrylic acid, crotonic acid, maleic acid, fumaric acid and itaconic acid; maleic anhydride, itaconic anhydride and the like. Unsaturated carboxylic acid anhydrides; hydroxyl groups such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, N-methylol (meth) acrylamide, 2-hydroxyethyl vinyl ether Containing vinyl monomer; 2-aminoethyl (meth) acrylate, 2-aminopropyl (meth) acrylate, 3-aminopropyl (meth) acrylate, 2-dimethylaminoethyl (meth) acrylate, 2-diethylaminoethyl (meth) ) Acrylate, 2-dimethylaminop Amino group-containing vinyl monomers such as pill (meth) acrylate, 3-dimethylaminopropyl (meth) acrylate, 2-aminoethyl vinyl ether, N, N-dimethylamino (meth) acrylamide, and N, N-diethylamino (meth) acrylamide 1,1,1-trimethylamine (meth) acrylimide, 1-methyl-1-ethylamine (meth) acrylimide, 1,1-dimethyl-1- (2-hydroxypropyl) amine (meth) acrylimide, 1,1-dimethyl-1- (2′-phenyl-2′-hydroxyethyl) amine (meth) acrylimide, 1,1-dimethyl-1- (2′-hydroxy-2′-phenoxypropyl) amine (meta ) Amineimide group-containing vinyl monomers such as acrylimide; Glycidyl (meth) acrylic Examples thereof include epoxy group-containing vinyl monomers such as rate and allyl glycidyl ether. These vinyl monomers having a functional group (α) can be used alone or in admixture of two or more.

Examples of other vinyl monomers copolymerizable with the vinyl monomer having a functional group (α) include styrene, α-methyl styrene, 4-methyl styrene, 2-methyl styrene, and 3-methyl styrene. 4-methoxystyrene, 2-hydroxymethylstyrene, 4-ethylstyrene, 4-ethoxystyrene, 3,4-dimethylstyrene, 3,4-diethylstyrene, 2-chlorostyrene, 3-chlorostyrene, 4-chloro- Aromatic vinyl monomers such as 3-methylstyrene, 4-t-butylstyrene, 2,4-dichlorostyrene, 2,6-dichlorostyrene, 1-vinylnaphthalene;
Methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, i-propyl (meth) acrylate, n-butyl (meth) acrylate, i-butyl (meth) acrylate, t-butyl (meth) (Meth) acrylate compounds such as acrylate, amyl (meth) acrylate, i-amyl (meth) acrylate, hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-octyl (meth) acrylate, and cyclohexyl methacrylate ;
Divinylbenzene, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, dipropylene glycol di (meth) ) Acrylate, tripropylene glycol di (meth) acrylate, tetrapropylene glycol di (meth) acrylate, butanediol di (meth) acrylate, hexanediol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tetra ( Polyfunctional monomers such as (meth) acrylates;
(Meth) acrylamide, N-methylol (meth) acrylamide, N-methoxymethyl (meth) acrylamide, N-butoxymethyl (meth) acrylamide, N, N′-methylenebisacrylamide, diacetone acrylamide, maleic acid amide, maleimide, Acid amide compounds such as crotonamide, maleic acid diamide, fumaric acid diamide, itaconic acid diamide, α-ethylacrylamide;
Vinyl compounds such as fatty acid vinyl esters such as vinyl chloride, vinylidene chloride, vinyl acetate and vinyl propionate;
1,3-butadiene, 2-methyl-1,3-butadiene, 2,3-dimethyl-1,3-butadiene, 2-neopentyl-1,3-butadiene, 2-chloro-1,3-butadiene, 2- Aliphatic conjugated dienes such as substituted linear conjugated pentadienes substituted with substituents such as cyano-1,3-butadiene, isoprene, alkyl groups, halogen atoms, cyano groups, linear and side chain conjugated hexadienes;
Vinyl cyanide compounds such as acrylonitrile and methacrylonitrile;
Fluorine atom-containing monomers such as trifluoroethyl (meth) acrylate and pentadecafluorooctyl (meth) acrylate;
4- (meth) acryloyloxy-2,2,6,6-tetramethylpiperidine, 4- (meth) acryloylamino-2,2,6,6-tetramethylpiperidine, 4- (meth) acryloyloxy-1, Piperidine monomers such as 2,2,6,6-pentamethylpiperidine;
2- (2′-hydroxy-5′-methacryloxyethylphenyl) -2H-benzotriazole, 2- (2′-hydroxy-3′-t-butyl-5′-methacryloxyethylphenyl) -2H-benzotriazole UV-absorbing monomers such as 2-hydroxy-4- (methacryloyloxyethoxy) benzophenone and 2-hydroxy-4- (acryloyloxyethoxy) benzophenone;
Examples include dicaprolactone. These can be used alone or in combination of two or more.

  As an unsaturated compound having a functional group (β) and a carbon / carbon double bond, for example, a vinyl monomer similar to the vinyl monomer having a functional group (α), or the above hydroxyl group-containing vinyl type An isocyanate group-containing unsaturated compound obtained by reacting a monomer and a diisocyanate compound in an equimolar amount can be exemplified.

Further, as the unsaturated silane compound used in the method (II), CH ₂ ═CHSi
(CH ₃ ) (OCH ₃ ) ₂ , CH ₂ = CHSi (OCH ₃ ) ₃ , CH ₂ = CHSi (CH ₃ ) Cl ₂ , CH ₂ = CHSiCl ₃ , CH ₂ = CHCOO (CH ₂ ) ₂ Si (CH ₃ ) (OCH ₃ ) ₂ ,
_{CH 2 = CHCOO (CH 2)} 2 Si (OCH 3) 3, CH 2 = CHCOO (CH 2) 3 Si (CH 3) (OCH 3) 2, CH 2 = CHCOO (CH 2) 3 Si (OCH 3) ₃ , CH ₂ = CHCO
_{O (CH 2) 2 Si (} CH 3) Cl 2, CH 2 = CHCOO (CH 2) 2 SiCl 3, CH 2 = C
_{HCOO (CH 2) 3 Si (} CH 3) Cl 2, CH 2 = CHCOO (CH 2) 3 SiCl 3, CH 2 = C (CH 3) COO (CH 2) 2 Si (CH 3) (OCH 3) 2 , CH ₂ = C (CH ₃ ) CO
O (CH ₂ ) ₂ Si (OCH ₃ ) ₃ , CH ₂ ═C (CH ₃ ) COO (CH ₂ ) ₃ Si (CH ₃ ) (
_{OCH 3) 2, CH 2 =} C (CH 3) COO (CH 2) 3 Si (OCH 3) 3, CH 2 = C (CH 3) COO (CH 2) 2 Si (CH 3) Cl 2, CH 2 _{= C (CH 3) COO (} CH 2) 2 SiCl 3, CH 2 = C (CH 3) COO (CH 2) 3 Si (CH 3) Cl 2, CH 2 = C (CH 3) CO
O (CH ₂ ) ₃ SiCl ₃ ,

Can be mentioned. These can be used alone or in combination of two or more. Examples of other vinyl monomers copolymerized with the unsaturated silane compound include, for example, vinyl monomers having the functional group (α) exemplified in the method (I-1) and other vinyl monomers. A monomer etc. can be mentioned.

  As a preferable example of the specific silyl group-containing polymer (C), the following formula (6)

(In the formula, R ⁷ represents a hydrogen atom or a methyl group, and R ⁸ represents a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, an i-butyl group, an n-pentyl group, n An alkyl group having 1 to 6 carbon atoms such as a hexyl group, R ⁹ is synonymous with R ⁷ , and R ¹⁰ is an alkylene group having 1 to 4 carbon atoms such as a methylene group, an ethylene group, a propylene group or a butylene group; R ¹¹ has the same meaning as R ⁸ , j and k represent the number of each repeating unit, and k / (j + k) = 0.01 to 0.4, preferably 0.02 to 0.2. .)
And a trialkoxysilyl group-containing (meth) acrylate copolymer represented by the formula:

  Other examples of the specific silyl group-containing polymer include a specific silyl group-containing epoxy resin, a specific silyl group-containing polyester resin, and a specific silyl group-containing fluororesin. Examples of the specific silyl group-containing epoxy resin include epoxy groups in epoxy resins such as bisphenol A type epoxy resin, bisphenol F type epoxy resin, hydrogenated bisphenol A type epoxy resin, aliphatic polyglycidyl ether, and aliphatic polyglycidyl ester. And aminosilanes having a specific silyl group, vinylsilanes, carboxysilanes, glycidylsilanes, and the like. The specific silyl group-containing polyester resin is produced, for example, by reacting a carboxyl group or a hydroxyl group contained in the polyester resin with aminosilanes, carboxysilanes, glycidylsilanes or the like having a specific silyl group. Can do. The specific silyl group-containing fluororesin reacts with, for example, a carboxyl group or a hydroxyl group contained in a (co) polymer such as ethylene fluoride with aminosilanes, carboxysilanes, glycidylsilanes or the like having a specific silyl group. Can be manufactured.

The polystyrene-reduced number average molecular weight (hereinafter referred to as “Mn”) of the specific silyl group-containing polymer (C) is preferably 2,000 to 100,000, more preferably 4,000 to 50,000. The weight average molecular weight in terms of polystyrene (hereinafter referred to as “Mw”) is preferably 2,000 to 100,000, and more preferably 4,000 to 50,000. The amount of the specific silyl group-containing polymer (C) used is usually 2 to 900 parts by weight, preferably 10 to 400 parts by weight, based on 100 parts by weight of the complete hydrolysis condensate of the silane compound (A). More preferably, it is 20-300 weight part. In this case, if the amount of the specific silyl group-containing polymer used is less than the above lower limit, the resulting photocatalyst layer may be inferior in alkali resistance, whereas if it exceeds the above upper limit, the long-term weather resistance of the photocatalyst layer is lowered. Tend to. The above and completely hydrolyzed condensate becomes a SiOH group and -OR ⁴ groups of 100% hydrolysis of the silane compound (A), further fully condensed refers to became siloxane structure.

  Examples of the polymerization method for producing the specific silyl group-containing polymer (C) include, for example, a method in which monomers are added all at once and polymerized, and a part of the monomers is polymerized and then the rest is continuously Or a method of adding the monomer continuously or intermittently, or a method of continuously adding the monomer from the beginning of the polymerization. Moreover, the polymerization method which combined these polymerization methods is also employable. A preferred polymerization method includes solution polymerization. As the solvent used for the solution polymerization, usual solvents can be used, and among them, ketones and alcohols are preferable. In this polymerization, known polymerization initiators, molecular weight regulators, chelating agents, and inorganic electrolytes can be used.

In the present invention, the specific silyl group-containing polymer (C) can be used alone or in admixture of two or more obtained as described above.
(D) Organosiloxane oligomer:
The organosiloxane oligomer (D) used in the present invention has a Si—O bond and has a weight average molecular weight of 300 to 100,000, preferably a hydroxyl group, a halogen atom, or an organic group having 1 to 15 carbon atoms. It is contained at the end, and more preferably, the side chain and / or the end is represented by the following formula (2)
-(RO) _p- (R'O) _q- R "(2)
(In the formula, R and R ′ each independently represent an alkyl group having 1 to 5 carbon atoms, R ″ represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and p and q each have a value of p + q. 2-50)
It has the structure represented by these. These groups may be partially hydrolyzed / condensed or substituted derivatives.

Examples of the halogen atom include fluorine and chlorine.
As an organic group having 1 to 15 carbon atoms, an alkyl group, acyl group, alkoxyl group, alkoxysilyl group, vinyl group, allyl group, acetoxyl group, acetoxysilyl group, cycloalkyl group, phenyl group, glycidyl group, (meth) acrylic Examples thereof include an oxy group, a ureido group, an amide group, a fluoroacetamide group, and an isocyanate group.

  Examples of the alkyl group having 1 to 15 carbon atoms include methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, i-butyl group, sec-butyl group, t-butyl group, and n-hexyl. Group, n-heptyl group, n-octyl group, n-nonyl group, n-decyl group, undecyl group, dodecyl group, tridecyl group, tetradecyl group, hexadecyl group, heptadecyl group, octadecyl group, 2-ethylhexyl group, etc. It is done.

Examples of the acyl group having 1 to 15 carbon atoms include formyl group, acetyl group, propionyl group, butyryl group, valeryl group, benzoyl group, and toluoyl group.
Examples of the alkoxyl group having 1 to 15 carbon atoms include a methoxy group, an ethoxy group, a propoxy group, and a butoxy group.

Examples of the alkoxysilyl group having 1 to 15 carbon atoms include a methoxysilyl group, an ethoxysilyl group, a propoxysilyl group, and a butoxysilyl group.
Examples of the functional group represented by the above formula (2) include polyoxyalkylene groups such as a polyoxyethylene group, a polyoxypropylene group, and a poly (oxyethylene / oxypropylene) group. It is considered that when the organosiloxane oligomer (D) contains such a functional group, the polyoxyalkylene group portion in the functional group is easily adsorbed to the photocatalyst (B), and the dispersion stability of the photocatalyst (B) is improved. It is done.

Examples of the substituent of the substituted derivative include a halogen atom, a substituted or unsubstituted amino group, a hydroxyl group, a mercapto group, an isocyanate group, a glycidoxy group, a 3,4-epoxycyclohexyl group, a (meth) acryloxy group, a ureido group, An ammonium base, a ketoester group, etc. are mentioned.

  Of these, the organosiloxane oligomer (D) containing a structure in which a silicon atom of a silyl group is bonded to a hydrolyzable group and / or a hydroxyl group is particularly preferably used. For example, a chlorosilane condensate or an alkoxysilane condensate is used. Used. Since such an organosiloxane oligomer (D) is co-condensed and immobilized with the silane compound (A) or the like when the photocatalyst composition is cured, a stable photocatalyst layer can be obtained.

  The weight average molecular weight (hereinafter also referred to as “Mw”) in terms of polystyrene by GPC method of the organosiloxane oligomer (D) is 300 to 100,000, preferably 600 to 50,000. When the weight average molecular weight is less than the above lower limit, the obtained photocatalyst layer may not obtain sufficient flexibility, and when it exceeds the above upper limit, the obtained photocatalyst composition may not exhibit sufficient storage stability. .

  In the present invention, the organosiloxane oligomer (D) may be used alone or in combination of two or more. As an organosiloxane oligomer (D) in which two or more kinds are mixed, a mixture of an organosiloxane oligomer having Mw = 400 to 2,800 and an organosiloxane oligomer having Mw = 3,000 to 50,000, or 2 having different functional groups Mention may be made of mixtures of different organosiloxane oligomers.

  In the present invention, a commercially available organosiloxane oligomer can be used as the organosiloxane oligomer (D). For example, a modified silicone oil manufactured by Toray Dow Corning Silicone, a modified silicone manufactured by GE Toshiba Silicone Oil, modified silicone oil manufactured by Shin-Etsu Chemical Co., Ltd., modified silicone oligomer MAC-2101 manufactured by Nihon Unicar, and hydroxyl group-containing polydimethylsiloxane manufactured by Dow Corning Asia. These organosiloxane oligomers may be used as they are or after being condensed.

  In the present invention, the amount of the organosiloxane oligomer (D) is 1 to 200 parts by weight, preferably 5 to 100 parts by weight, more preferably 10 to 80 parts by weight with respect to 100 parts by weight of the solid content of the photocatalyst (B). Is desirable. When the amount of the organosiloxane oligomer (D) is less than the above lower limit, sufficient dispersion stability may not be obtained. When the amount exceeds the above upper limit, the content of the photocatalyst (B) decreases and the photocatalytic activity decreases. Therefore, sufficient photocatalytic action may not be obtained.

  Moreover, the ratio of the silane compound (A) and the organosiloxane oligomer (D) is silane with respect to a total amount of 100% by weight in terms of complete hydrolysis condensate of the silane compound (A) and the organosiloxane oligomer (D). Compound (A) is 5 to 95% by weight in terms of complete hydrolysis condensate, preferably 10 to 90% by weight, and organosiloxane oligomer (D) is 95 to 5% by weight in terms of complete hydrolysis condensate, preferably 90 to 90%. 10% by weight. When the silane compound (A) is less than the lower limit, the resulting photocatalyst composition may not be sufficiently cured, and when the upper limit is exceeded, the crack resistance of the photocatalyst layer may be reduced.

In the present invention, the organosiloxane oligomer (D) is usually co-hydrolyzed and condensed with the silane compound (A). In this case, the amount of water used for hydrolysis / condensation of the silane compound (A) or (organosiloxane oligomer (D) is usually 0 with respect to 1 mol of OR ² group contained in the silane compound (A). 2 mol or more, preferably 0.3 mol or more, more preferably 0.4 to 2 mol In addition, when an aqueous dispersion of a semiconductor compound is used as the photocatalyst (B), The water present can be used for the hydrolysis of the silane compound (A) and the organosiloxane oligomer (D) In this case, the hydrolysis / condensation reaction, that is, the reaction conditions during the preparation of the photocatalyst composition, is a temperature of 30. -80 ° C., preferably 40-70 ° C., reaction time is 0.5-10 hours, preferably 1-7 hours In the photocatalyst composition used in the present invention, the silane compound (A The weight average molecular weight of the cohydrolyzed condensate (hydrolyzate and / or condensate thereof) when cohydrolyzed and condensed with the organosiloxane oligomer (D) is usually 500 to 100,000, preferably 600. ~ 80,000.

(E) Titanium compound:
The titanium compound (E) used in the present invention has the following formula (3)
(R ³ ) _m Ti (OR ⁴ ) _4-m (3)
(Wherein R ³ represents an organic group having 1 to 8 carbon atoms, and when there are a plurality of them, they may be the same or different, and R ⁴ is an alkyl group having 1 to 6 carbon atoms, It represents an organic group selected from the group consisting of an acyl group having 1 to 6 carbon atoms and a phenyl group, and when there are a plurality of them, they may be the same or different, and R ³ and R ⁴ are the same Or m may be an integer of 0 to 3)
A titanium alcoholate, a hydrolyzate of the titanium alcoholate, a condensate of the titanium alcoholate and a condensate of the chelate compound of the titanium alcoholate, and a titanium acylate represented by the above formula (1), It is at least one titanium compound selected from the group consisting of a hydrolyzate of the titanium acylate, a condensate of the titanium acylate, and a condensate of the chelate compound of the titanium acylate.

In the above formula (3), R ³ is an organic group having 1 to 8 carbon atoms, specifically, methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, sec- Alkyl groups such as butyl group, t-butyl group, n-pentyl group, n-hexyl group, n-heptyl group, n-octyl group, 2-ethylhexyl group;
Acyl groups such as formyl group, acetyl group, propionyl group, butyryl group, valeryl group, benzoyl group, trioyl group, caproyl group;
Examples thereof include a vinyl group, an allyl group, a cyclohexyl group, a phenyl group, an epoxy group, a glycidyl group, a (meth) acryloxy group, a ureido group, an amide group, a fluoroacetamide group, and an isocyanate group.

Furthermore, examples of R ³ include substituted derivatives of the above organic groups. Examples of the substituent of the substituted derivative of R ³ include a halogen atom, a substituted or unsubstituted amino group, a hydroxyl group, a mercapto group, an isocyanate group, a glycidoxy group, a 3,4-epoxycyclohexyl group, a (meth) acryloxy group, A ureido group, an ammonium base, etc. are mentioned. However, the number of carbon atoms of R ³ composed of these substituted derivatives is preferably 8 or less including the carbon atoms in the substituent. When a plurality of R ³ are present in the formula (3), they may be the same or different from each other.

As R ⁴ which is an alkyl group having 1 to 6 carbon atoms, for example, a methyl group, an ethyl group, n
-Propyl group, i-propyl group, n-butyl group, i-butyl group, sec-butyl group, t-butyl group, n-hexyl group, n-heptyl group and the like can be mentioned.

Examples of R ⁴ which is an acyl group having 1 to 6 carbon atoms include formyl group, acetyl group, propionyl group, butyryl group, valeryl group, trioyl group, caproyl group and the like.
When a plurality of R ⁴ are present in the formula (3), they may be the same or different.

  The chelate compound of titanium alcoholate is selected from the group consisting of the titanium alcoholate and β-diketones, β-ketoesters, hydroxycarboxylic acid, hydroxycarboxylate, hydroxycarboxylic acid ester, ketoalcohol and aminoalcohol. It can be obtained by reacting with at least one compound (hereinafter also referred to as chelating agent). A chelate compound of titanium acylate can be obtained by reacting the titanium acylate with the chelating agent. Of these chelating agents, β-diketones or β-ketoesters are preferably used. More specifically, acetylacetone, methyl acetoacetate, ethyl acetoacetate, acetoacetate-n-propyl, acetoacetate-i-propyl, acetoacetate-n-butyl, acetoacetate-sec-butyl, acetoacetate-t-butyl 2,4-hexane-dione, 2,4-heptane-dione, 3,5-heptane-dione, 2,4-octane-dione, 2,4-nonane-dione, 5-methyl-hexane-dione, etc. Used.

  Specific examples of titanium alcoholate and titanium alcoholate chelate compounds include tetra-i-propoxytitanium, tetra-n-butoxytitanium, tetra-t-butoxytitanium, and di-i-propoxybis (ethylacetoacetate). Titanium, di-i-propoxy bis (acetylacetate) titanium, di-i-propoxy bis (lactate) titanium, di-i-propoxy bis (acetylacetonato) titanium, di-n-butoxy bis (tri Ethanolaminato) titanium, di-n-butoxy bis (acetylacetonato) titanium, tetrakis (2-ethylhexyloxy) titanium and the like.

  Of these, tetra-i-propoxytitanium, tetra-n-butoxytitanium, tetra-t-butoxytitanium, di-i-propoxybis (acetylacetonato) titanium, di-n-butoxybis (acetylacetonate) ) Titanium is preferred.

  Specific examples of titanium acylate and titanium acylate chelate compounds include dihydroxy / titanium dibutyrate, di-i-propoxy / titanium diacetate, bis (acetylacetonate) / titanium diacetate, and bis (acetylacetate). Nato) -titanium dipropionate, di-i-propoxy-titanium dipropionate, di-i-propoxy-titanium dimalonate, di-i-propoxy-titanium dibenzoylate, di-n-butoxy-zirconium diacetate , Di-i-propyl aluminum monomalonate and the like. Of these, dihydroxy titanium dibutyrate and di-i-propoxy titanium diacetate are preferred.

Titanium alcoholate hydrolyzate, titanium alcoholate chelate hydrolyzate, titanium acylate hydrolyzate, or titanium acylate chelate hydrolyzate is contained in titanium alcoholate or titanium acylate at least one oR ⁴ groups need only be hydrolysed, for example those in which one oR ⁴ group is hydrolyzed, those two or more oR ⁴ group is hydrolyzed, or a mixture thereof May be.

  Titanium alcoholate condensate, titanium alcoholate chelate condensate, titanium acylate condensate, and titanium acylate chelate condensate are titanium alcoholate, titanium alcoholate chelate, titanium acylate, respectively. The Ti—OH group in the hydrolyzate produced by hydrolysis of the rate and the chelate compound of titanium acylate is condensed to form a Ti—O—Ti bond. In the present invention, it is not necessary that all of the Ti—OH groups are condensed, and the condensate is obtained by condensing a small part of Ti—OH groups, and most (including all) Ti—OH groups. In addition, a mixture of a condensate in which a Ti—OR group and a Ti—OH group are mixed is also included.

In the present invention, it is preferable to use the condensate as the titanium compound (E) in order to control reactivity and suppress gelation, and the average degree of condensation of the condensate is 2 to 20, that is, the condensation The product is more preferably a dimer to a 20-mer, and the average degree of condensation is preferably 2 to 10, that is, the condensate is particularly preferably a dimer to a 10-mer. This condensate is composed of titanium alcoholate, titanium alcoholate chelate compound, titanium acylate, and one compound selected from the group consisting of titanium acylate chelate compounds or a mixture of two or more titanium compounds. Those previously hydrolyzed and condensed may be used, or commercially available condensates may be used. In addition, a titanium alcoholate or a titanium acylate condensate may be used as it is, a product obtained by hydrolyzing a part or all of the OR ⁴ group contained in the condensate, or the chelate obtained by chelating the condensate. You may use as a condensate of the chelate compound of titanium alcoholate or titanium acylate obtained by making it react with an agent.

  Examples of commercially available condensates of titanium alcoholate (from dimer to decamer) include A-10, B-2, B-4, B-7, and B-10 manufactured by Nippon Soda Co., Ltd. It is done. Such a titanium compound (E) may be used individually by 1 type, or 2 or more types may be mixed and used for it.

The amount of the titanium compound (E) used in the present invention is 1 to 100 parts by weight, preferably 2 to 90 parts by weight, in terms of complete hydrolysis condensate, based on 100 parts by weight of the solid content of the photocatalyst (B). The amount is preferably 3 to 80 parts by weight. Here, the completely hydrolyzed condensate means that the OR ⁴ group in the formula (3) is 100% hydrolyzed to become a Ti—OH group, and further the Ti—OH group is completely condensed to form a Ti—O—Ti structure. Is what formed. These titanium compounds (E) adsorb or bind to the surface of the photocatalyst (B), improve the affinity of the photocatalyst (B) to the solvent, reduce the dispersed particle size, and increase dispersibility. It is believed that there is.

(Water and organic solvents)
The photocatalyst composition used in the present invention preferably contains water and / or an organic solvent. The water contained in the photocatalyst composition is usually subjected to hydrolysis / partial condensation reaction of the silane compound (A), the organosiloxane oligomer (D), or the like when preparing the photocatalyst composition, or the photocatalyst (B) or the like. It is added to disperse the particulate component. The usage-amount of the water in this invention is 0.5-3 mol normally with respect to 1 mol of total of a silane compound (A) and an organosiloxane oligomer (D), Preferably it is 0.7-2 mol.

  In addition, the organic solvent uniformly mixes each component of the photocatalyst composition, adjusts the total solid concentration of the photocatalyst composition, and at the same time, can be applied to various coating methods, and also provides dispersion stability of the photocatalyst composition and Used to further improve storage stability. Examples of such organic solvents include alcohols, aromatic hydrocarbons, ethers, ketones, and esters.

More specifically, as alcohols, methanol, ethanol, n-propyl alcohol, i-propyl alcohol, n-butyl alcohol, sec-butyl alcohol, t-butyl alcohol, n-hexyl alcohol, n-octyl alcohol, ethylene Glycol, diethylene glycol, triethylene glycol, ethylene glycol monobutyl ether, ethylene glycol monoethyl ether acetate, diethylene glycol monoethyl ether, propylene glycol monomethyl ether, propylene monomethyl ether acetate, diacetone alcohol, and the like. As aromatic hydrocarbons, Benzene, toluene, xylene and the like, and ethers include tetrahydrofuran, dioxane and the like, Examples of tones include acetone, methyl ethyl ketone, methyl isobutyl ketone, diisobutyl ketone and the like. Examples of esters include ethyl acetate, propyl acetate, butyl acetate, propylene carbonate, methyl lactate, ethyl lactate, normal propyl lactate, isopropyl lactate, 3 -Methyl ethoxypropionate, ethyl 3-ethoxypropionate and the like. These organic solvents may be used alone or in combination of two or more.

  Among such organic solvents, an organic solvent having a surface tension at 20 ° C. of 260 μN / cm or less is preferable. Since such an organic solvent has a low surface tension, the resulting photocatalyst composition has good wettability with respect to the substrate, so that the so-called “repellency phenomenon” hardly occurs, and the film formability of the obtained coating film Is excellent. Examples of such an organic solvent include methyl alcohol, ethyl alcohol, n-propyl alcohol, i-propyl alcohol, i-butyl alcohol, methyl ethyl ketone, methyl isobutyl ketone, and butyl acetate.

  In the present invention, in addition to an organic solvent having a surface tension (20 ° C.) of 260 μN / cm or less, an organic solvent having a surface tension at 20 ° C. exceeding 260 μN / cm is used as an average surface tension (20 ° C.) of all organic solvents. Can be used as long as the amount is 260 μN / cm or less, for example, 20% by weight or less in the total organic solvent. When an organic solvent having a surface tension (20 ° C.) exceeding 260 μN / cm is used in excess of 20% by weight, the surface tension of the whole organic solvent may become too high, and the resulting photocatalyst composition may repel the substrate. May occur. Examples of such an organic solvent include ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monoethyl ether, and cyclohexanone.

(catalyst)
The photocatalyst composition used in the present invention preferably contains a catalyst for promoting hydrolysis / condensation reaction such as silane compound (A) and organosiloxane oligomer (D). By using such a catalyst, the curing rate of the photocatalyst composition is increased, and the molecular weight of the polysiloxane resin produced by the polycondensation reaction of the silane compound or titanium compound used is increased. A photocatalyst layer excellent in durability and the like can be obtained, and the photocatalyst layer can be made thicker, so that the painting operation is facilitated.

  As a catalyst used in the present invention, an acidic compound, an alkaline compound, a salt compound, an amine compound, an organometallic compound and / or a partial hydrolyzate thereof (hereinafter referred to as an organometallic compound and / or a partial hydrolyzate thereof, Organic metal compounds ”).

Examples of the acidic compound include acetic acid, hydrochloric acid, sulfuric acid, phosphoric acid, alkyl titanic acid, p-toluenesulfonic acid, and phthalic acid, and among these, acetic acid is preferable.
Examples of the alkaline compound include sodium hydroxide and potassium hydroxide, and among these, sodium hydroxide is preferable.

Examples of the salt compound include naphthenic acid, octylic acid, nitrous acid, sulfurous acid, aluminate, and alkali metal salts such as carbonic acid.
Examples of the amine compound include ethylenediamine, hexamethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, piperidine, piperazine, m-phenylenediamine, p-phenylenediamine, ethanolamine, triethylamine, 3-aminopropyl trimethoxy. Silane, 3-aminopropyl-triethoxysilane, 3- (2-aminoethyl) -aminopropyl-trimethoxysilane, 3- (2-aminoethyl) -aminopropyl-triethoxysilane, 3- (2-aminoethyl) ) -Aminopropyl-methyl-dimethoxysilane, 3-anilinopropyl-trimethoxysilane, alkylamine salts, and quaternary ammonium salts. Various modified amines used as a curing agent for epoxy resins can also be used. Of these, 3-aminopropyl-trimethoxysilane, 3-aminopropyl-triethoxysilane, 3- (2-aminoethyl) -aminopropyl-trimethoxysilane, 3- (2-aminoethyl) -aminopropyl- Triethoxysilane is preferred.

Examples of the organometallic compounds include the following formula (7):
M (OR ¹² ) _r (R ¹³ COCHCOR ¹⁴ ) _s (7)
(In the formula, M represents at least one metal atom selected from the group consisting of zirconium, titanium and aluminum, and R ¹² and R ¹³ are each independently a methyl group, an ethyl group, an n-propyl group, C1-C6 monovalent hydrocarbon group such as i-propyl group, n-butyl group, sec-butyl group, t-butyl group, n-pentyl group, n-hexyl group, cyclohexyl group, phenyl group R ¹⁴ represents the aforementioned monovalent hydrocarbon group having 1 to 6 carbon atoms, or a methoxy group, an ethoxy group, an n-propoxy group, an i-propoxy group, an n-butoxy group, a sec-butoxy group, represents an alkoxyl group having 1 to 16 carbon atoms such as t-butoxy group, lauryloxy group and stearyloxy group, and r and s are each independently an integer of 0 to 4, and (r + s) = (M atom ) Satisfy the relationship)
(Hereinafter referred to as “organometallic compound (7)”),
A tetravalent tin organometallic compound in which one or two alkyl groups having 1 to 10 carbon atoms are bonded to one tin atom (hereinafter referred to as “organotin compound”), or
These partial hydrolysates are exemplified.

Moreover, the above-described titanium compound (b) can be used as the organometallic compounds.
Examples of the organometallic compound (7) include tetra-n-butoxyzirconium, tri-n-butoxyethylacetoacetatezirconium, di-n-butoxybis (ethylacetoacetate) zirconium, n-butoxytris (ethylacetoacetate). Organic zirconium compounds such as acetate) zirconium, tetrakis (n-propylacetoacetate) zirconium, tetrakis (acetylacetoacetate) zirconium, tetrakis (ethylacetoacetate) zirconium;
Organic titanium compounds such as tetra-i-propoxy titanium, di-i-propoxy bis (ethylacetoacetate) titanium, di-i-propoxy bis (acetylacetate) titanium, di-i-propoxy bis (acetylacetone) titanium ;
Tri-i-propoxyaluminum, di-i-propoxyethyl acetoacetate aluminum, di-i-propoxy acetylacetonate aluminum, i-propoxy bis (ethylacetoacetate) aluminum, i-propoxy bis (acetylacetonate) And organoaluminum compounds such as aluminum, tris (ethylacetoacetate) aluminum, tris (acetylacetonato) aluminum, monoacetylacetonatobis (ethylacetoacetate) aluminum.

Among these organometallic compounds (4) and partial hydrolysates thereof, tri-n-butoxy ethylacetoacetate zirconium, di-i-propoxy bis (acetylacetonato) titanium, di-i-propoxy ethylacetate Acetate aluminum, tris (ethyl acetoacetate) aluminum, or a partial hydrolyzate thereof is preferably used.
(C ₄ H ₉ ) ₂ Sn (OCOC ₁₁ H ₂₃ ) ₂ ,
_{(C 4 H 9) 2 Sn} (OCOCH = CHCOOCH 3) 2,
_{(C 4 H 9) 2 Sn} (OCOCH = CHCOOC 4 H 9) 2,
(C ₈ H ₁₇ ) ₂ Sn (OCOC ₈ H ₁₇ ) ₂ ,
(C ₈ H ₁₇ ) ₂ Sn (OCOC ₁₁ H ₂₃ ) ₂ ,
_{(C 8 H 17) 2 Sn} (OCOCH = CHCOOCH 3) 2,
_{(C 8 H 17) 2 Sn} (OCOCH = CHCOOC 4 H 9) 2,
_{(C 8 H 17) 2 Sn} (OCOCH = CHCOOC 8 H 17) 2,
_{(C 8 H 17) 2 Sn} (OCOCH = CHCOOC 16 H 33) 2,
_{(C 8 H 17) 2 Sn} (OCOCH = CHCOOC 17 H 35) 2,
_{(C 8 H 17) 2 Sn} (OCOCH = CHCOOC 18 H 37) 2,
_{(C 8 H 17) 2 Sn} (OCOCH = CHCOOC 20 H 41) 2,

_{(C 4 H 9) Sn (} OCOC 11 H 23) 3,
(C ₄ H ₉ ) Sn (OCONa) ₃
Carboxylic acid type organotin compounds such as;
_{(C 4 H 9) 2 Sn} (SCH 2 COOC 8 H 17) 2,
_{(C 4 H 9) 2 Sn} (SCH 2 CH 2 COOC 8 H 17) 2,
_{(C 8 H 17) 2 Sn} (SCH 2 COOC 8 H 17) 2,
_{(C 8 H 17) 2 Sn} (SCH 2 CH 2 COOC 8 H 17) 2,
_{(C 8 H 17) 2 Sn} (SCH 2 COOC 12 H 25) 2,
_{(C 8 H 17) 2 Sn} (SCH 2 CH 2 COOC 12 H 25) 2,
_{(C 4 H 9) Sn (} SCOCH = CHCOOC 8 H 17) 3,
_{(C 8 H 17) Sn (} SCOCH = CHCOOC 8 H 17) 3,

Mercaptide-type organotin compounds such as
(C ₄ H ₉ ) ₂ Sn = S, (C ₈ H ₁₇ ) ₂ Sn = S,

Sulfide-type organotin compounds such as;
(C ₄ H ₉ ) SnCl ₃ , (C ₄ H ₉ ) ₂ SnCl ₂ ,
(C ₈ H ₁₇ ) ₂ SnCl ₂ ,

Chloride-type organotin compounds such as;
Reaction of organotin oxides such as (C ₄ H ₉ ) ₂ SnO, (C ₈ H ₁₇ ) ₂ SnO, and ester compounds such as silicates, dimethyl maleate, diethyl maleate and dioctyl phthalate Product;
Etc.

Such a catalyst may be used singly or in combination of two or more, or may be used by mixing with a zinc compound or other reaction retarder.
The catalyst may be blended in the step of preparing the photocatalyst composition used in the present invention, may be blended in the photocatalyst composition in the step of forming the photocatalyst layer, and further, the photocatalyst composition is prepared. You may mix | blend both in a process and the formation process of a photocatalyst layer.

The amount of the catalyst used in the present invention is usually 10 mol or less, preferably 0.001 to 7 mol, more preferably 0.001 to 5 mol per mol of OR ² group contained in the silane compound (A). Mole is desirable. When the amount of the catalyst exceeds the above upper limit, the storage stability of the photocatalyst composition may be lowered, or cracks may occur in the photocatalyst layer.

  Such a catalyst accelerates the hydrolysis / condensation reaction of the silane compound (A), the organosiloxane oligomer (D) and the like. Therefore, by using the above catalyst, for example, the molecular weight of the polysiloxane resin produced by the polycondensation reaction of the organosiloxane oligomer (D) is increased, the curing rate of the photocatalyst composition is improved, and the strength and durability are increased. In addition, a photocatalyst layer excellent in the thickness of the photocatalyst layer can be obtained, and the photocatalyst layer can be made thicker, so that the painting operation is facilitated.

(Stability improver)
The photocatalyst composition used in the present invention can contain a stability improver as necessary in order to improve storage stability and the like. The stability improver used in the present invention is represented by the following formula (8).
R ¹⁵ COCH ₂ COR ¹⁶ (8)
(In the formula, R ¹⁵ is methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, sec-butyl group, t-butyl group, n-pentyl group, n-hexyl group, cyclohexyl group) R 1 represents a monovalent hydrocarbon group having 1 to 6 carbon atoms such as a phenyl group or the like, and R ¹⁶ represents a monovalent hydrocarbon group having 1 to 6 carbon atoms, or a methoxy group, an ethoxy group, n -Represents an alkoxyl group having 1 to 16 carbon atoms such as propoxy group, i-propoxy group, n-butoxy group, sec-butoxy group, t-butoxy group, lauryloxy group, stearyloxy group)
At least one compound selected from the group consisting of β-diketones, β-ketoesters, carboxylic acid compounds, dihydroxy compounds, amine compounds and oxyaldehyde compounds.

Examples of such stability improvers include acetylacetone, methyl acetoacetate, ethyl acetoacetate, acetoacetate-n-propyl, acetoacetate-i-propyl, acetoacetate-n-butyl, acetoacetate-sec-butyl, Acetoacetate-t-butyl, hexane-2,
4-dione, heptane-2,4-dione, heptane-3,5-dione, octane-2,4-dione, nonane-2,4-dione, 5-methylhexane-2,4-dione, malonic acid, Oxalic acid, phthalic acid, glycolic acid, salicylic acid, aminoacetic acid, iminoacetic acid, ethylenediaminetetraacetic acid, glycol, catechol, ethylenediamine, 2,2-bipyridine, 1,10-phenanthroline, diethylenetriamine, 2-ethanolamine, dimethylglyoxime, Examples include dithizone, methionine, and salicylaldehyde. Of these, acetylacetone and ethyl acetoacetate are preferred.

  Such a stability improver is particularly preferably used when a titanium compound (E) or an organometallic compound is used as a catalyst. Moreover, a stability improver may be used individually by 1 type, or 2 or more types may be mixed and used for it.

  By using the stability improver, the stability improver is coordinated to the metal atom of the organometallic compound, and this coordination is organic for the co-condensation reaction of the silane compound (A) or the organosiloxane oligomer (D). It is considered that the storage stability of the resulting photocatalyst composition can be further improved by appropriately adjusting the promoting action of the metal compounds.

  The amount of the stability improver used in the present invention is usually 2 moles or more, preferably 3 to 20 moles per mole of the organometallic compound of the organometallic compounds. When the amount of the stability improver is less than the above lower limit, the effect of improving the storage stability of the resulting composition may be insufficient in a photocatalyst composition having a high solid content concentration.

(Inorganic compounds)
The photocatalyst composition used in the present invention may contain a powder and / or a sol or colloid of an inorganic compound having no photocatalytic activity other than the photocatalyst (B) as necessary. Such inorganic compounds include SiO ₂ , Al ₂ O ₃ , AlGaAs, Al (OH
) ₃ , Sb ₂ O ₅ , Si ₃ N ₄ , Sn—In ₂ O ₃ , Sb—In ₂ O ₃ , MgF, CeF ₃ , CeO ₂ , 3Al ₂ O ₃ .2SiO ₂ , BeO, SiC, AlN, Fe Fe ₂ O ₃ , Co, Co—FeO _x , CrO ₂ , Fe ₄ N, BaTiO ₃ , BaO—Al ₂ O ₃ —SiO ₂ , Ba ferrite, SmCO ₅ , YCO ₅ , CeCO ₅ , PrCO ₅ , Sm ₂ CO ₁₇ , Nd ₂ Fe ₁₄ B, ZrO ₂
Al ₄ O ₃ , AlN, SiC, α-Si, SiN ₄ , CoO, Sb—SnO ₂ , Sb ₂ O ₅ , MnO ₂ , MnB, Co ₃ O ₄ , Co ₃ B, LiTaO ₃ , MgO, MgAl ₂ O ₄ , BeAl ₂ O ₄ , ZrSiO ₄ , ZnSb, PbTe, GeSi, FeSi ₂ , CrSi ₂ , CoSi ₂
, MnSi _1.73 , Mg ₂ Si, β-B, BaC, BP, TiB ₂ , ZrB ₂ , HfB ₂ , Ru ₂ Si ₃ , TiO ₃ , PbTiO ₃ , Al ₂ TiO ₅ , Zn ₂ SiO ₄ , Zr ₂ SiO _{4 , 2MgO 2 -Al 2 O 3 -5SiO} 2, Nb 2 O 5, Li 2 O-Al 2 O 3 -4SiO 2, Mg ferrite, Ni ferrite, Ni-Zn ferrite, Li ferrite, etc. Sr ferrite. These inorganic compounds can be used individually by 1 type or in mixture of 2 or more types.

The form of the inorganic compound is preferably a powder, an aqueous sol or colloid dispersed in water, or a solvent sol or colloid dispersed in a polar solvent such as isopropyl alcohol or a nonpolar solvent such as toluene. In the case of a solvent-based sol or colloid, depending on the dispersibility of the semiconductor, it may be further diluted with water or a solvent, or may be used after a surface treatment to improve the dispersibility. When the inorganic compound is an aqueous sol or colloid and a solvent sol or colloid, the solid content concentration is preferably 40% by weight or less. As a method of blending the above-mentioned inorganic compound into the photocatalyst composition, it may be added after mixing other components to prepare the photocatalyst composition, or a photocatalyst composition is prepared together with other components, and the inorganic compound is added. Further, it may be cohydrolyzed and partially condensed with the silane compound (A) or the like. The amount of the inorganic compound used is usually 0 to 500 parts by weight, preferably 0.1 to 400 parts by weight in terms of solid content, with respect to a total of 100 parts by weight in terms of complete hydrolysis condensate of the silane compound (A). is there.

(filler)
In the photocatalyst composition used in the present invention, it is also preferable to add and disperse a filler as necessary in order to color the obtained photocatalyst layer and to increase the thickness of the film.

  Fillers used in the present invention include water-insoluble organic pigments and inorganic content; ceramics, metals or alloys other than particulate, fibrous or scale-like pigments, and oxides, hydroxides and carbides of these metals , Nitrides and sulfides.

  Specifically, iron, copper, aluminum, nickel, silver, zinc, ferrite, carbon black, stainless steel, silicon dioxide, titanium oxide for pigments, aluminum oxide, chromium oxide, manganese oxide, iron oxide, zirconium oxide, cobalt oxide , Synthetic mullite, aluminum hydroxide, iron hydroxide, silicon carbide, silicon nitride, boron nitride, clay, diatomaceous earth, slaked lime, gypsum, talc, barium carbonate, calcium carbonate, magnesium carbonate, barium sulfate, bentonite, mica, zinc green , Chrome green, Cobalt green, Viridian, Guinea green, Cobalt chrome green, Shale green, Green earth, Manganese green, Pigment green, Ultramarine, Bitumen, Pigment blue, Rock ultramarine, Cobalt blue, Cerulean blue, Copper borate, Molybdenum blue , Copper sulfide, cobalt purple, mars purple, manga Purple, Pigment Violet, Lead Oxide, Calcium Leadate, Zinc Yellow, Lead Sulfide, Chrome Yellow, Ocher, Cadmium Yellow, Strontium Yellow, Titanium Yellow, Resurge, Pigment Yellow, Cuprous Oxide, Cadmium Red, Selenium Red, Chrome Vermilion , Bengala, zinc white, antimony white, basic lead sulfate, titanium white, lithopone, lead silicate, zircon oxide, tungsten white, lead, zinc white, bunchison white, lead phthalate, manganese white, lead sulfate, graphite, bone Black, diamond black, thermatomic black, vegetable black, potassium titanate whisker, molybdenum disulfide, and the like.

These fillers can be used alone or in admixture of two or more.
Moreover, the usage-amount of a filler has preferable 300 weight part or less with respect to 100 weight part of total solid of the visible light photocatalyst composition used for this invention.

(Other additives)
In the visible light photocatalyst composition used in the present invention, if necessary,
Known dehydrating agents such as methyl orthoformate, methyl orthoacetate, tetraethoxysilane;
Polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, polyoxyethylene fatty acid ester, polycarboxylic acid type polymer surfactant, polycarboxylate, polyphosphate, polyacrylate, polyamide ester salt, polyethylene glycol, etc. A dispersant of
Celluloses such as methylcellulose, ethylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, hydroxypropylmethylcellulose, thickeners such as castor oil derivatives, ferrosilicates;
Inorganic foaming agents such as ammonium carbonate, ammonium hydrogen carbonate, ammonium nitrite, sodium borohydride, calcium azide;
Organic foaming agents such as azo compounds such as azobisisobutyronitrile, hydrazine compounds such as diphenylsulfone-3,3′-disulfohydrazine, semicarbazide compounds, triazole compounds, N-nitroso compounds;
Other additives such as a surfactant, a silane coupling agent, a titanium coupling agent, and a dye can also be blended.

Moreover, in order to improve the coating property (it is also called film forming property) of the composition used for this invention, a leveling agent can be mix | blended. As such leveling agents, for example, BM1000 (trade name, hereafter the same) and BM1100 manufactured by BM-CHEMIE; EFKA 772 and EFKA 777 manufactured by EFKA Chemicals; Floren series manufactured by Kyoeisha Chemical Co., Ltd .; Sumitomo Fluorine leveling agents such as 3M's FC series; Toho Chemical's Fluoronal TF series;
BYK series from Big Chemie; Sshmego series from Sshmegmann; silicones such as Fuka 30, Fuka 31, Fuka 34, Fuka 35, Fuka 36, Fuka 39, Fuka 83, Fuka 86, and Fuka 88 from Fuka Chemicals Leveling agents;
Carfinol from Nissin Chemical Industry Co., Ltd .; Ether-type or ester-type leveling agents such as emulgen and homogenol from Kao Corporation.

  By blending such a leveling agent, the finished appearance of the photocatalyst layer can be improved and a uniform thin film can be prepared. In the present invention, the leveling agent is preferably used in an amount of 0.01 to 5% by weight, more preferably 0.02 to 3% by weight, based on the entire photocatalyst composition.

  The method of blending the leveling agent may be blended in the step of preparing the photocatalyst composition used in the present invention, may be blended in the photocatalyst composition in the step of forming the photocatalyst layer, and further the photocatalyst composition. You may mix | blend both in the preparation process of this, and the formation process of a photocatalyst layer.

(Method for preparing photocatalyst composition)
The photocatalyst composition used in the present invention is prepared by mixing the above-mentioned components and subjecting them to hydrolysis and partial condensation. Specifically, the following methods can be mentioned.

  (1) A predetermined amount of a mixture comprising a silane compound (A), a photocatalyst (B), a necessary amount of an organic solvent, and a specific silyl group-containing polymer (C) and an organosiloxane oligomer (D) as necessary. A method of carrying out hydrolysis and partial condensation reaction by adding water and a catalyst.

  (2) After mixing a part of the predetermined amount of the silane compound (A), the photocatalyst (B) and the required amount of the organic solvent, the remaining silane compound (A) and, if necessary, the specific silyl group-containing weight A method in which a coalescence (C) and an organosiloxane oligomer (D) are added and mixed, and a predetermined amount of water and a catalyst are added thereto to carry out a hydrolysis / partial condensation reaction.

  (3) A mixture of a photocatalyst (B), a titanium compound (E) and a necessary amount of an organic solvent, and, if necessary, a specific silyl group-containing polymer (C) and an organosiloxane oligomer (D) are added to a silane compound ( A) and a method in which a predetermined amount of water and a catalyst are added to perform a hydrolysis and partial condensation reaction.

  Examples of the disperser used when mixing the photocatalyst (B) of the above production method include an ultrasonic disperser, a ball mill, a sand mill (bead mill), a homogenizer, an ultrasonic homogenizer, a nanomizer, a propeller mixer, and a high shear mixer. .

  Moreover, in the said manufacturing method (3), the secondary particle size (dispersion particle size) of a photocatalyst (B) falls by disperse | distributing a photocatalyst (B) with a disperser in presence of a titanium compound (E). Further, when the organosiloxane oligomer (D) is used, the photocatalyst (B) is fixed in the organosiloxane oligomer (D) by adsorbing with the structure represented by the above formula (2) of the organosiloxane oligomer (D). Dispersion stability is ensured.

And by adding a silane compound (A) as needed, a silane compound (A) plays the role of a binder, and even when there is much content of a photocatalyst (B), it can form into a film without choking. .

  The total solid content concentration in the photocatalyst composition used in the present invention can be appropriately set according to the type of base material, the coating method, the thickness of the coating film, etc., for example, usually exceeding 0% by weight to 50 % By weight or less, preferably 0.01% by weight or more and 20% by weight or less, more preferably 0.05% by weight or more and 10% by weight or less. When the total solid content exceeds the above upper limit, the storage stability may be lowered.

<Coating composition for undercoat>
The photocatalytic sheet according to the present invention has a deterioration preventing intermediate layer between the base material and the photocatalyst layer in order to prevent the base material from being deteriorated by the photocatalytic action of the photocatalyst layer. The intermediate layer is not particularly limited as long as it can prevent deterioration of the substrate. For example, the intermediate layer may be formed using the following undercoat coating composition (hereinafter also referred to as “undercoat composition”). it can.
(I) A composition containing a silane compound and a specific silyl group-containing polymer.
(Ii) A composition comprising a silane compound, a specific silyl group-containing polymer, and at least one of colloidal silica and colloidal alumina.
(Iii) A composition containing a silane compound, a specific silyl group-containing polymer, and at least one of colloidal cerium oxide and colloidal zinc oxide.
(Iv) A composition comprising a silane compound, a specific silyl group-containing polymer, at least one of colloidal silica and colloidal alumina, and at least one of colloidal cerium oxide and colloidal zinc oxide.

  As the silane compound used in the undercoat coating composition, the silane compounds exemplified as the silane compound (A) used in the photocatalyst composition can be used, and the same as the silane compound (A) used in the photocatalyst composition. However, from the viewpoint of adhesion between the intermediate layer and the photocatalyst layer, it is preferable to use a silane compound composed of the same organosilane.

  Further, the specific silyl group-containing polymer used in the coating composition for undercoat can be the specific silyl group-containing polymer exemplified as the specific silyl group-containing polymer (C) used in the photocatalyst composition. Although it may be the same as or different from the specific silyl group-containing polymer (C) used in the composition, the same specific silyl group-containing polymer is used from the viewpoint of adhesion between the intermediate layer and the photocatalyst layer. It is preferable.

The undercoat compositions (i) to (iv) are preferably co-condensed with a silane compound and a specific silyl group-containing polymer in the presence of water and / or an organic solvent. In this case, the amount of water, relative to the -OR ² 1 mole of the silane compound is usually 0.2 mol or more, preferably 0.
About 3 to 2 moles. Here, the undercoat compositions (i) to (iv) are usually used in a form dissolved and dispersed in water and / or an organic solvent.

  The organic solvent is not particularly limited as long as each component can be mixed uniformly, and the organic solvents exemplified as the organic solvent used in the photocatalyst composition can be used. Moreover, these organic solvents can be used individually or in mixture of 2 or more types.

  Each of the undercoat compositions (i) to (iv) may further contain a catalyst similar to that used in the photocatalyst composition, a stability improver, and an inorganic compound that does not exhibit photocatalytic ability, if necessary. it can.

Further, the undercoating compositions (i) to (iv) may be blended with an ultraviolet absorber other than cerium oxide and zinc oxide, an ultraviolet stabilizer, and the like for the purpose of improving weather resistance and durability adhesion. Examples of the ultraviolet absorber include inorganic semiconductors such as TiO ₂ (not showing a photocatalytic function); organic ultraviolet absorbers such as salicylic acid, benzophenone, benzotriazole, cyanoacrylate, and triazine. Examples of the ultraviolet stabilizer include piperidine-based ultraviolet stabilizer.

  The undercoating compositions (i) to (iv) are blended with resins such as acrylic-urethane resins, epoxy resins, polyesters, acrylic resins, fluororesins, acrylic resin emulsions, epoxy resin emulsions, polyurethane emulsions, and polyester emulsions. May be.

  The total solid content concentration of the undercoat compositions (i) to (iv) is usually more than 0% by weight and 50% by weight or less, preferably 0.01% by weight or more and 40% by weight or less. It is adjusted as appropriate according to the coating method, coating film thickness, and the like.

[Photocatalytic sheet]
The photocatalytic sheet according to the present invention is a photocatalytic sheet comprising a base material having light diffusibility, an intermediate layer provided on the base material, and a photocatalytic layer provided on the intermediate layer. The “sheet” in the present invention is a concept including a film.

  The substrate used in the present invention includes an organic substrate having light diffusibility and flexibility such as a fluororesin sheet containing fine particles; a light diffusibility and flexibility such as a silicone resin sheet and glass fiber fabric containing fine particles. An inorganic base material having These base materials preferably have a total light transmittance of 40% or more, more preferably 45% or more, particularly preferably 50% or more, and a parallel light transmittance of preferably 10% or less, more preferably 5%. It is as follows.

  The resin sheet containing the fine particles can be obtained by molding a resin composition containing a fluororesin, a silicone resin, or the like and fine particles such as glass beads into a sheet shape. Examples of the glass fiber fabric include, for example, JP-A-6-192937, JP-A-8-195114, JP-A-8-246292, JP-A-8-259637, JP-A-8-290528, Examples thereof include glass fiber fabrics described in JP-A-8-306215, JP-A-2001-55646, JP-A-2003-3375, and JP-A-2003-171848.

  The photocatalytic sheet according to the present invention includes an intermediate layer formed from the undercoat composition provided on the substrate, and a photocatalyst layer formed from the photocatalyst composition provided on the intermediate layer. And have. Such a photocatalytic sheet is flexible even if the base material, the intermediate layer formed from the undercoating composition, and the photocatalyst layer formed from the photocatalyst composition are flexible. The cracks of each layer and the cracks of each layer are not easily generated, it has excellent bending resistance, and can be suitably used for bending. Specifically, in the cylindrical mandrel test described in JIS K5600-5-1, the photocatalytic sheet has a minimum radius of a mandrel that does not generate cracks in the intermediate layer and the photocatalytic layer, preferably 10 mm or less, preferably 8 mm or less. More preferably, it is 5 mm or less.

  Moreover, in this invention, you may form a nonflammable resin layer between the said base material and an intermediate | middle layer according to various uses. Examples of the incombustible resin layer include a fluororesin layer and a silicone resin layer.

<Method for producing photocatalytic sheet>
The photocatalytic sheet according to the present invention can be produced, for example, by the following method. First, the undercoat composition is formed on a substrate, and this coating film is dried to form an intermediate layer. Next, the photocatalyst composition is formed on the intermediate layer, and the coating film is dried to form a photocatalyst layer. Further, after forming a fluororesin layer on the substrate, the undercoat composition is formed on the fluororesin layer and dried to form an intermediate layer, and then the photocatalyst composition is formed on the intermediate layer. May be formed and dried to form a photocatalyst layer.

  At this time, in order to accelerate the curing rate of the intermediate layer and the photocatalyst layer, a curing catalyst may be appropriately added to the undercoat composition and the photocatalyst composition as necessary. In particular, when the coating film is dried at a low temperature of 100 ° C. or lower, it is preferable to use a curing catalyst. As the curing catalyst, a compound similar to the catalyst used in the photocatalyst composition can be used. In order to form an intermediate layer or a photocatalyst layer having a desired thickness, the undercoat composition or the photocatalyst composition may be appropriately diluted with a solvent such as an organic solvent or water to form a film.

  As a method of forming a film for an undercoating composition or a photocatalyst composition, for example, coating using a brush, roll coater, bar coater, flow coater, centrifugal coater, ultrasonic coater, (micro) gravure coater, etc .; dip coating; sink Coating; spraying; screen process; electrodeposition; vapor deposition and the like.

  After forming an undercoating composition or photocatalyst composition by these methods, the coating film is dried at room temperature or at a temperature of about 30 to 200 ° C., usually for 1 to 60 minutes, so that a stable intermediate layer or photocatalyst is formed. A layer can be formed.

  When the undercoat composition and the photocatalyst composition used in the present invention are formed into a film, the dry film thickness is about 0.05 to 20 μm in the case of a single application, and the dry film thickness is 0.1 to 40 μm in the case of a double application. A film of a degree can be formed.

  In this invention, in order to ensure the adhesiveness of a base material and an intermediate | middle layer, you may apply various primers previously. The kind of primer is not specifically limited, What is necessary is just to have the effect | action which improves the adhesiveness of a base material and an undercoat composition, and it selects according to the kind of base material and the intended purpose. The primer may be used alone or in admixture of two or more, and may be an enamel containing a coloring component such as a pigment or a clear containing no such coloring component.

  Examples of the primer include alkyd resins, amino alkyd resins, epoxy resins, polyesters, acrylic resins, urethane resins, fluororesins, acrylic silicone resins, acrylic resin emulsions, epoxy resin emulsions, polyurethane emulsions, and polyester emulsions. . These primers can also be provided with various functional groups when adhesion between the substrate and the coating film under severe conditions is required. Examples of such a functional group include a hydroxyl group, a carboxyl group, a carbonyl group, an amide group, an amine group, a glycidyl group, an alkoxysilyl group, an ether bond, and an ester bond. Further, the primer may contain an ultraviolet absorber, an ultraviolet stabilizer and the like.

The photocatalytic sheet according to the present invention not only has a photocatalytic action and flexibility, but also has nonflammability, and the base material has light diffusibility, so that it can be applied to a lighting cover.
[Lighting device]
The illuminating device according to the present invention is an illuminating device including an artificial light source and an illumination cover in which the photocatalytic sheet is fixed to a support, and the base of the photocatalytic sheet is the artificial light source, the photocatalytic layer, An artificial light source and a lighting cover are provided so as to exist between the two. Specifically, an artificial light source such as a fluorescent lamp is provided inside the illumination device, and an illumination cover in which the photocatalytic sheet is fixed to a support is attached so as to cover the artificial light source. At this time, the layer structure of the photocatalytic sheet is an inorganic base / intermediate layer / photocatalyst layer in order from the inside of the lighting device, that is, the artificial light source side. Therefore, in the lighting device according to the present invention, the outermost layer is a photocatalyst layer, and thus impurities and organic substances attached to the lighting cover can be easily decomposed and removed by the photocatalytic action.

[Example]
EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not limited at all by this Example. “Parts” and “%” represent “parts by weight” and “% by weight”, respectively, unless otherwise specified.

<Preparation of specific silyl group-containing polymer (C)>
[Reference Example 1]
In a reactor equipped with a reflux condenser and a stirrer, 55 parts of methyl methacrylate, 5 parts of 2-ethylhexyl acrylate, 5 parts of cyclohexyl methacrylate, 10 parts of γ-methacryloxypropyltrimethoxysilane, 20 parts of glycidyl methacrylate, 4- (meth) 5 parts of acryloyloxy-2,2,6,6-tetramethylpiperidine, 75 parts of i-butyl alcohol, 50 parts of methyl ethyl ketone and 25 parts of methanol were added and mixed. The mixture was then heated to 80 ° C. with stirring, a solution of 3 parts of azobisisovaleronitrile dissolved in 8 parts of xylene was added dropwise over 30 minutes, and reacted at 80 ° C. for 5 hours to obtain a solid content. A specific silyl group-containing polymer (C) solution having a concentration of 40% and Mw of 12,000 was obtained.

<Preparation of photocatalyst composition>
[Preparation Example A1]
In a reactor equipped with a stirrer and a reflux condenser, 100 parts of methyltrimethoxysilane as the silane compound (A) and an aqueous sol of titanium oxide as the photocatalyst (B) (40% titanium oxide, 40% water, 20% alcohol) 100 parts, 200 parts of isopropyl alcohol as a solvent, and 4 parts of di-i-propoxy-ethylacetoacetate aluminum as a catalyst were added and mixed. The mixture was subjected to a condensation reaction for 4 hours while stirring at 60 ° C. Subsequently, after cooling to room temperature, 493 parts of i-propyl alcohol was added to obtain a photocatalyst composition (I-1) having a solid concentration of about 10%.

[Preparation Example A2]
In a reactor equipped with a stirrer and a reflux condenser, 21 parts of methyltrimethoxysilane as a silane compound (A) and 200 parts of water-dispersed titanium oxide having a solid concentration of 24.5% as a photocatalyst (B) are added and mixed. The mixture was further stirred at 30 ° C. for 1 hour. Then, 39 parts of silane compound (A) methyltrimethoxysilane and 7 parts of γ-glycididoxypropyltrimethoxysilane, bifunctional containing terminal alkoxysilyl group / poly (oxyethylene / oxypropylene) group as organosiloxane oligomer (D) 15 parts of an oligomer (manufactured by Nippon Unicar Co., Ltd., trade name: MAC2101) and 82 parts of i-propyl alcohol as a solvent were added and mixed, and further stirred at 30 ° C. for 1 hour. Thereafter, a solution of 3 parts of di-i-propoxy / ethyl acetoacetate aluminum dissolved in 15 parts of i-propyl alcohol was added and mixed as a catalyst, and further a co-condensation reaction was performed for 4 hours while stirring at 60 ° C. Next, 4 parts of acetylacetone was added and stirred for 1 hour, and then cooled to room temperature. Thereafter, 600 parts of i-propyl alcohol was added to obtain a photocatalyst composition (I-2) having a solid concentration of about 10%.

[Preparation Example A3]
In a reactor equipped with a stirrer and a reflux condenser, 85 parts of methyltrimethoxysilane as the silane compound (A) and an aqueous sol of titanium oxide as the photocatalyst (B) (40% titanium oxide, 40% water, 20% alcohol) 100 parts of the above-mentioned specific silyl group-containing polymer (C)
C) 20 parts of isopropyl alcohol as a solvent and 200 parts of di-I-propoxy-ethylacetoacetate aluminum as a catalyst were added and mixed, and a co-condensation reaction was carried out for 4 hours while stirring at 60 ° C. Thereafter, the mixture was cooled to room temperature, and 495 parts of i-propyl alcohol was added to obtain a photocatalyst composition (I-3) having a solid concentration of about 10%.

[Preparation Example A4]
In a reactor equipped with a stirrer and a reflux condenser, 8 parts of 3-glycidoxypropyltrimethoxysilane as a silane compound (A) and an anatase type water dispersion oxidation with a solid content concentration of 24.5% as a photocatalyst (B) 200 parts of titanium (pH 3, average particle size 50 nm), and 11 parts of terminal alkoxysilyl group / poly (oxyethylene / oxypropylene) group-containing oligomer (made by Nihon Unicar Company, trade name: MAC2101) are added as organosiloxane oligomer (D). The mixture was further stirred at 30 ° C. for 10 minutes. Thereafter, 22 parts of i-propyl alcohol having a surface tension of 217 μN / cm at 20 ° C. was added and mixed as a solvent, and the mixture was further stirred at 30 ° C. for 1 hour. Thereafter, 60 parts of methyltrimethoxysilane as the silane compound (A) and 23 parts of the specific silyl group-containing polymer (C) as the polymer (C) were added and mixed, and further stirred at 30 ° C. for 1 hour. Thereafter, a solution prepared by dissolving 3 parts of di-i-propoxyethylacetoacetate aluminum in 79 parts of i-propyl alcohol as a catalyst was added and mixed, and further a co-condensation reaction was performed for 4 hours while stirring at 60 ° C. Next, after cooling to room temperature, 600 parts of i-propyl alcohol was added to obtain a photocatalyst composition (I-4) having a solid concentration of about 10%.

[Preparation Example A5]
100 parts of titanium dioxide having a platinum compound as the photocatalyst (B), 56 parts of tetra-n-butoxytitanium decamer (product name: B-10, manufactured by Nippon Soda Co., Ltd.) as the titanium compound (E), isopropyl alcohol as the solvent 700 parts were put into a container, 600 parts of zirconia beads having a particle diameter of 0.3 mm were added, and the mixture was stirred and dispersed for 1 hour using a bead mill.

  Next, after removing the beads, 96 parts of methyltrimethoxysilane as a silane compound (A) was added to the dispersion and stirred sufficiently, and then 4 parts of di-i-propoxyethylacetoacetate aluminum as a catalyst and water 12 After stirring for 4 hours at 60 ° C., isopropyl alcohol was added to obtain a photocatalyst composition (I-5) having a solid concentration of about 10%.

[Preparation Example A6]
In a reactor equipped with a stirrer and a reflux condenser, 42 parts of ethyl silicate 48, 67 parts of IPA-dispersed colloidal silica (solid content concentration 30%), an aqueous sol of titanium oxide (40% titanium oxide, 40% water, alcohol) 20%) 100 parts and 591 parts of isopropyl alcohol were added to obtain a photocatalyst composition (I-6) having a solid concentration of about 10%.

[Comparative Preparation Example A1]
Coating composition (I-7) having a solid content concentration of about 10% in the same manner as in Preparation Example A4, except that titanium oxide was not used and the amount of isopropyl alcohol added after cooling was changed from 600 parts to 310 parts. Got.

<Preparation of undercoat composition>
[Preparation Example B1]
In a reactor equipped with a stirrer and a reflux condenser, 71 parts of methyltrimethoxysilane, 24 parts of dimetholdimethoxysilane, 125 parts of the specific silyl group-containing polymer (C) having a solid content of 40%, i-propyl alcohol 34 Part, 15 parts of methyl ethyl ketone, and 3 parts of di-I-propoxy-ethyl acetoacetate aluminum were added and mixed, and the temperature was raised to 50 ° C. with stirring. To this mixture, 17 parts of water was added dropwise over 30 minutes, and then reacted at 60 ° C. for 4 hours. Next, 4 parts of acetylacetone was added and stirred for 1 hour, and then cooled to room temperature. Then
While stirring, 592 parts of methyl isobutyl ketone, 20 parts of ethylene glycol monobutyl ether, 95 parts of isopropyl alcohol, and 150 parts of MIBK-dispersed cerium oxide (solids concentration 10%) are added to form a coating composition for undercoating of about 10% solids concentration. A product (i-1) was obtained.

[Preparation Example B2]
In a reactor equipped with a stirrer and a reflux condenser, 41 parts of methyltrimethoxysilane, 16 parts of dimetholdimethoxysilane, 175 parts of the specific silyl group-containing polymer (C) having a solid content of 40%, and i-propyl alcohol 31 Part, 13 parts of methyl ethyl ketone and 3 parts of di-I-propoxy-ethyl acetoacetate aluminum were added and mixed, and the temperature was raised to 50 ° C. with stirring. To this mixture, 10 parts of water was added dropwise over 30 minutes, and then reacted at 60 ° C. for 4 hours. Next, 4 parts of acetylacetone was added and stirred for 1 hour, and then cooled to room temperature. Next, with stirring, 317 parts of methyl ethyl ketone, 75 parts of butyl acetate, 20 parts of ethylene glycol monobutyl ether, 295 parts of isopropyl alcohol, and 150 parts of IPA-dispersed colloidal silica (solid content concentration 10%) are added to obtain a solid content concentration of about 10 % Undercoat coating composition (i-2) was obtained.

[Base material preparation example]
Glass fibers having a count of 22.5 tex were used for both the warp and the weft, and the weft density of the warp was 236/10 cm, and the weave density of the weft was 180 / 10cm. Thereafter, fiber opening was performed by a vibro washer to obtain a glass fiber fabric. The basis weight of this glass fiber fabric is 93.6 g / m ² , the thickness is 85 μm, and the air permeability is 18 cm ³ / (cm ² · s.
)Met.

  Next, a soft fluororesin (Shuran Soft G-180Y manufactured by Central Glass Co., Ltd.) was dissolved in N, N-dimethylformamide so that the solid content was 18% by weight, and isocyanate (Coronate HX manufactured by Dainippon Ink & Chemicals, Inc.) was dissolved. ) Was added in an amount of 0.5 parts by weight to 100 parts by weight of the soft fluororesin to prepare a fluororesin solution. After impregnating the fluororesin solution with the glass fiber fabric, the glass fiber fabric was dried by heating.

  On the other hand, 100 parts by weight of a soft fluororesin (Central Glass Co., Ltd., Furansoft G-180Y), 5 parts by weight of vinylidene fluoride resin, 0.2 parts by weight of polytetrafluoroethylene, 0.3 parts by weight of wax, dibutyltin dilaurate 0.2 parts by weight and 1.0 part by weight of hollow glass beads (HSC-100C manufactured by Toshiba Barotini Co., Ltd.) were blended and formed into a sheet.

  This sheet was bonded to the glass fiber woven fabric treated with the fluororesin solution to obtain a light diffusing sheet comprising a fluororesin layer and the glass fiber woven fabric. This light diffusing sheet had a total light transmittance of 59.4% and an equilibrium light transmittance of 4.3%.

[Examples 1 to 7 and Comparative Example 1]
To 100 parts of the undercoat coating composition (i-1) or (i-2), 5 parts of an i-propyl alcohol solution of dioctyltin dimaleate ester (solid content 15%) was added, and a sufficiently stirred solution was added. Each of the substrates shown in Table 1 was coated with a bar coater so as to have a dry film thickness of 1 μm and dried to form an intermediate layer on the light diffusing sheet.

Next, 100 parts of the photocatalyst compositions (I-1) to (I-6) or the coating composition (I-7) were mixed with an i-propyl alcohol solution (solid content concentration of 15) of a reaction product comprising dibutyltin diacetate and a silicate oligomer. %) 3 parts of the mixture was added, and the well-stirred solution was coated on the intermediate layer with a bar coater so that the dried coating film was 1 μm and dried to produce a photocatalytic sheet. The flexible sheet was evaluated for flexibility, durability, and acetaldehyde decomposability by the following methods. The results are shown in Table 1.

(Flexibility (flexibility) evaluation)
A cylindrical mandrel test was conducted according to JIS K5600-5-1 and evaluated according to the following criteria.

A: No crack at a radius of 5 mm or more B: Crack generation at a radius of 5 mm, no crack at a radius of 8 mm or more C: Crack generation at a radius of 10 mm (Durability evaluation)
The photocatalytic sheet was irradiated for 500 hours with a metal weather (temperature 63 ° C., humidity 40% RH, irradiation intensity 80 mW / cm ² ) manufactured by Daipura Wintes. This photocatalyst sheet was visually observed and evaluated according to the following criteria. Moreover, the tape peeling test was implemented using the cellophane tape (brand name: cello tape (R) No. 405) by Nichiban, and adhesiveness was evaluated on the following reference | standard.
(Appearance) A: No change from before irradiation
C: Base material turns yellow (adhesion) A: No peeling of photocatalyst layer and intermediate layer
B: Photocatalyst layer partially peeled
C: All photocatalyst layers peeled off (Acetaldehyde decomposition evaluation)
A 1-liter Tedlar bag was charged with a photocatalytic sheet and sealed, and then 150 ppm of acetaldehyde was injected into the Tedlar bag. This photocatalytic sheet was irradiated with 15000 Lxs light for 12 hours with a daylight white fluorescent lamp, and the acetaldehyde residual amount and carbon dioxide increase after irradiation were measured by gas chromatography (FID detection).

Claims (11)

A photocatalytic sheet comprising a base material having light diffusivity, an intermediate layer provided on the base material, and a photocatalytic layer provided on the intermediate layer,
In the mandrel test, the photocatalytic sheet has a minimum radius of a mandrel in which cracks do not occur in the intermediate layer and the photocatalyst layer of 10 mm or less,
The photocatalytic layer is
(A) The following formula (1)
(R ¹ ) _n Si (OR ² ) _4-n (1)
(In the formula, R ¹ represents a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms, and when a plurality of R ¹ exist, they may be the same or different. R ² has 1 carbon atom. Represents an alkyl group of ˜5, an acyl group of 1 to 6 carbon atoms or a phenyl group, n is an integer of 0 to 2).
And at least one silane compound selected from the group consisting of a hydrolyzate of the organosilane and a condensate of the organosilane, and (B) a photocatalyst composition containing a photocatalyst. A photocatalytic sheet characterized by being a layer.   The photocatalytic sheet according to claim 1, wherein the base material is a fluororesin sheet containing fine particles, a silicone resin sheet containing fine particles, or a glass fiber fabric.   The photocatalytic sheet according to claim 1 or 2, wherein n in the formula (1) is 1 or 2.   The said photocatalyst composition contains the polymer (C) containing the silyl group which has a silicon atom couple | bonded with the hydrolyzable group and / or the hydroxyl group further, The any one of Claims 1-3 characterized by the above-mentioned. Photocatalytic sheet.   The photocatalyst composition according to any one of claims 1 to 4, wherein the photocatalyst composition further comprises an organosiloxane oligomer (D) having a SiO bond and a weight average molecular weight of 300 to 100,000. Sex sheet. The organosiloxane oligomer (D) is represented by the following formula (2)
-(RO) _p- (R'O) _q- R "(2)
(In the formula, R and R ′ each independently represent an alkyl group having 1 to 5 carbon atoms, R ″ represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and p and q each have a value of p + q. The photocatalytic sheet according to claim 5, having a structure represented by 2 to 50). The photocatalytic composition further comprises:
(E) The following formula (3)
(R ³ ) _m Ti (OR ⁴ ) _4-m (3)
(Wherein R ³ represents an organic group having 1 to 8 carbon atoms, and when there are a plurality of them, they may be the same or different, and R ⁴ is an alkyl group having 1 to 6 carbon atoms, It represents an organic group selected from the group consisting of an acyl group having 1 to 6 carbon atoms and a phenyl group, and when there are a plurality of them, they may be the same or different, and R ³ and R ⁴ are the same Or m may be an integer of 0 to 3)
A titanium alcoholate, a hydrolyzate of the titanium alcoholate, a condensate of the titanium alcoholate and a condensate of the chelate compound of the titanium alcoholate, and a titanium acylate represented by the above formula (1), It contains at least one kind of titanium compound selected from the group consisting of a hydrolyzate of the titanium acylate, a condensate of the titanium acylate, and a condensate of the chelate compound of the titanium acylate. The photocatalytic sheet according to any one of 1 to 6. The intermediate layer has the following formula (1)
(R ¹ ) _n Si (OR ² ) _4-n (1)
(In the formula, R ¹ represents a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms, and when a plurality of R ¹ exist, they may be the same or different. R ² has 1 carbon atom. Represents an alkyl group of ˜5, an acyl group of 1 to 6 carbon atoms or a phenyl group, n is an integer of 0 to 2).
And at least one silane compound selected from the group consisting of organosilane hydrolysates and organosilane partial condensates, and hydrolyzable groups and / or silicon bonded to hydroxyl groups The photocatalytic sheet according to any one of claims 1 to 7, further comprising a layer formed from a coating composition for undercoat containing a polymer containing a silyl group having an atom.   The photocatalytic sheet according to any one of claims 1 to 8, wherein the total light transmittance of the substrate is 40% or more and the parallel light transmittance is 10% or less.   The photocatalytic sheet according to claim 1, further comprising a fluororesin layer between the intermediate layer and the base material. An illumination device comprising an artificial light source and an illumination cover in which the photocatalytic sheet according to any one of claims 1 to 10 is fixed to a support,
An illumination device comprising an artificial light source and an illumination cover so that a base material of the photocatalytic sheet exists between the artificial light source and the photocatalyst layer.